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Your question : dopamine

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dopamine result rearranged

• Definition ( X is NP )
  • As a chemical messenger, dopamine is similar to adrenaline.
  • Dopamine [C8H11NO2], a hormone-like substance, is an important neurotransmitter.
  • Dopamine is a biogenic amine synthesized in the hypothalamus, in the arcuate nucleus, the caudad, and various areas of the central and peripheral nervous system.
  • Dopamine is a neurotransmitter, a chemical messenger between nerve cells in the mammalian brain.
  • Dopamine is a neurotransmitter, a chemical messenger in the nervous system.
  • Dopamine is a neurotransmitter (a chemical used to transmit impulses between nerve cells), mainly found in the brain.
  • Dopamine, a sympathomimetic amine vasopressor, is the naturally occurring immediate precursor of norepinephrine.
  • Action/Kinetics: Dopamine is the immediate precursor of epinephrine in the body.
  • NOTE: Dopamine is a potent drug.
  • Dopamine is a neurotransmitter (a chemical used to transmit impulses between nerve cells), mainly found in the brain.
  • Dopamine is a monoaminergic neurotransmitter.
  • Background: Dopamine- or dopa-responsive dystonia (DRD), also known as hereditary progressive dystonia with diurnal variation (HPD), is an inherited dystonia typically presenting in the first decade of life.
  • Dopamine(DA) is the principal neurotransmitter in three major neural systems in the midbrain : 1) the nigrostriatal pathway which originates from dopamine-synthesising neurons of the midbrain substantia nigra complex and innervates the dorsal striatum (caudate-putamen), and whose degeneration leads to Parkinson's disease); 2) the mesolimbic system which arises in the midbrain ventral tegmental area and innervates the ventral striatum (nucleus accumbens and olfactory tubercle) and part of the limbic system - this system influences motivated behaviour, including activity related to reward; 3) the ventral tegmental area also gives rise to the smaller mesocortical pathway, which innervates part of the frontal cortex and may be involved in certain aspects of learning and memory.
• X + is + non-NP
  • While all the research seems to indicate that dopamine is somehow involved in the production of the symptoms of schizophrenia, it is difficult to determine the exact involvment.
  • After the dopamine is released from the vesicles into the synaptic cleft, the remaining molecules are taken back into the synaptic terminal by transporters in the membrane.
  • Dopamine is also thought to produce feelings of bliss (the pleasure chemical).
  • Dopamine is found in three major pathways in the central nervous system.
  • Dopamine is produced from tyrosine by the action of TH, which uses BH4 as a cofactor.
• X + is + not + NP
  • Dopamine isn't itself the magic pleasure-chemical, though its functional role is crucial.
• X + is + not + non-NP
• X + verb
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    • Regulation of dopamine plays a crucial role in our mental and physical health.
    • It has been widely established that dopamine and its agonists play an important role in cardiovascular, renal, hormonal, and central nervous system regulation through stimulation of alpha and beta adrenergic and dopaminergic receptors.
    • UPTON, NY -- Dopamine, a brain chemical associated with addiction to cocaine, alcohol, and other drugs, may also play an important role in obesity.
    • Brookhaven scientists have done extensive research showing that dopamine plays an important role in drug addiction.
    • Dopamine acts as a reward for behaviour that precedes its release, and subsequently it triggers pursuit of the same reward after its release.
    • From a neurobiological perspective, some nerve cells do emit spontaneous bursts of electrical activity, and dopamine can increase the frequency of cell bursting, but only when it is applied immediately after the burst6 (akin to a reward for behaviour).
    • However, dopamine taken back into the nerve ending can return to the vesicle for storage.
    • Dopamine binds to its receptors quickly.
    • Dopamine and basal ganglia disorders in humans.
    • The first evidense that dopamine may be involved in schizophrenia came from amphetamine users.
    • According to this view, dopamine would not mediate the reinforcing effect of cocaine, but instead would underlie the motivational/arousing effects of seeing, say, the cocaine-spoon.
    • Dopamine can improve sex drive.
    • The Crowd: There's a repeat screening of 28 Days Later over at the Eccles Center and Dopamine can't quite compete.
    • Dopamine moves into frontal lobe regulating flow of information coming in from other areas of the brain.
    • In milder disorders, too much dopamine in the limbic system and not enough in the cortex may produce an overly suspicious personality giving to bouts of paranoia or may inhibit social interaction.
    • When the transporter is missing, dopamine lingers outside cells, stimulating them "100 to 300 times longer" than normal, Caron said.
    • In the body, dopamine exerts some control over locomotion, cognition and certain social behavior, Caron said, noting that locomotion is the easiest to assess in lab animals.
    • Dopamine can have either an excitatory or inhibitory effect on the postsynaptic potential.
    • The question of whether dopamine improves outcome for term infants with suspected perinatal asphyxia has not been answered.
    • It seems that dopamine represents both the chicken and the egg in the events underlying behavioural reinforcement.
    • An opposite effect occurs after dopamine or dopamine agonists repeatedly stimulate dopamine receptors.
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    • As a result, more dopamine remains to stimulate neurons, which causes a prolonged feelings of pleasure and excitement.
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    • Dopamine must be diluted in an appropriate sterile parenteral solution before intravenous administration.
    • Plays different roles: Dopamine in the basil ganglia (in brains interior) show they are critical for executing smooth and controlled movements.
    • Dopamine can be further metabolized to norepinephrine by the enzyme dopamine-b-hydroxylase, in neurons containing the enzyme.
• verb + X (mainly objective)
  • Administering reserpine causes dopamine to remain exposed within the cell and broken down by MAO.
  • As a result, the brains of people with Parkinson's disease contain almost no dopamine.
  • As mentioned earlier, people with Parkinson's disease lose neurons that contain dopamine.
  • Interestingly, one form of MAO actually protects dopamine.
  • Cocaine prevents dopamine reuptake by binding to proteins that normally transport dopamine.
  • Not only does cocaine "bully" dopamine out of the way-it hangs on to the transport proteins much longer than dopamine does.
  • Amphetamines work by causing the brain to produce more dopamine and have been shown to produce psychotic-like symptoms.
  • In PD the neural cells which produce dopamine deteriorate.
  • It is not possible to administer dopamine itself as a drug because it will not pass the blood-brain barrier between the blood vessels and neurons.
  • Last year, Malenka and his colleagues gave cocaine to mice and found that glutamate, a chemical in the body, was stimulating neurons in the VTA to release dopamine, a key neurotransmitter or message-carrying chemical associated with movement.
  • Multiple administrations of methamphetamine rapidly (within 1 h) decreased vesicular dopamine uptake and dihydrotetrabenazine binding, an effect that (a) persisted at least 24 h, (b) was associated with dopamine and not serotonin neurons, and (c) was unrelated to residual drug introduced by the original methamphetamine treatment.
  • Vitamin B-6 is also needed to make serotonin, melatonin, and dopamine.
  • This document titled "Parkinson's and Dopamine" covers the chemical dopamine, and how the lack of this chemical is associated with Parkinson's disease.
  • The transporter works by mopping up circulating dopamine that has already stimulated brain cells.
  • The findings, which will appear in the February 3, 2001 issue of The Lancet, imply that obese people may eat more to try to stimulate the dopamine "pleasure" circuits in their brains, just as addicts do by taking drugs.
  • Optimal management probably depends on correcting inflammation, increasing dopamine, and decreasing 5-HT levels.
  • Selection criteria: Randomised controlled trials comparing dopamine with placebo, no treatment, other inotropic agents, or volume in infants greater than 36 weeks gestation.
  • Yet the brain spares no dopamine with drugs such as cocaine, which bypass these dopamine-conserving mechanisms and increase dopamine release regardless of whether or not the drug reward is anticipated.
  • The better the drug is at blocking dopamine, the better it is at reducing the schizophrenia.
  • The proposed hypothesis states that the brain of schizophrenic patients produces more dopamine than normal brains.
  • Some drugs increase dopamine by preventing dopamine reuptake, leaving more dopamine in the synapse.
  • Controlling dopamine and dopamine receptors is essential for the treatment of schizophrenia.
• is + X
  • One of the neurotransmitters playing a major role in addiction is dopamine.
  • It is this increased dopamine that is believed to be responsible for the symptoms of the disease.
  • The major catecholamines are dopamine, norepinephrine, and epinephrine (old name: adrenalin).
  • Of particular interest is dopamine since this neurotransmitter seems to regulate food intake by modulating food reward via the meso-limbic circuitry of the brain.
• preposition + X
  • ¿µÇâ, È¿°ú, ÀÛ¿ë, ¿ªÇÒ, ¿ëµµ (Causal)
  • with/without
    • Seven infants only were randomised to treatment with dopamine and seven to receive placebo.
    • Efficacy of brain-derived neurotrophic factor and neurotrophin-3 on neurochemical and behavioral deficits associated with partial nigrostriatal dopamine lesions.
    • Synthesis and biological evaluation of novel amides of polyunsaturated fatty acids with dopamine.
  • of
    • A drug named reserpine prevents the reuptake of dopamine and some other neurotransmitters.
    • This increases the stores of dopamine and slows the progression of Parkinson's disease.
    • Furthermore, both drugs increase the amount of dopamine in the synapse.
    • One of the most significant findings of the last decade has been that of the association between the release of dopamine in the brain and reward or reinforcement.
    • Animals will push levers to deliver electric stimuli to their brains if those stimuli cause the release of dopamine.
    • PD is treated with L-dopa which is a precursor for the production of dopamine in the brain.
    • Schizophrenia is treated with drugs which block the binding of dopamine to its postsynaptic receptor sites.
    • It appears that the increased levels of dopamine in the striatum are responsible for some of the positive symptoms, particularly the overactivity.
    • Both the positive and negative emotional symptoms can be explained by the activity of dopamine in the limbic system.
    • One researcher hypothesizes that during normal development, activity of dopamine in one region of the brain may have an inhibitory effect on the development of other dopaminergic pathways.
    • Parkinson's disease (PD) is believed to be caused by a deficiency of dopamine.
    • A variety of small molecules, such as glutamate, GABA, and dopamine, can serve as a neurotransmitter.
    • L-DOPA is a precursor in the biosynthesis of dopamine in nerve cells, and causes the remaining dopaminergic cells to increase the production of dopamine.
    • The depletion of dopamine disbalances the direct and indirect pathways from the striatum, which causes the thalamus to be overstimulated.
    • Given the observations in the basal ganglia in the early1960's Birkmayer and Hornykiewics reasoned that it would possibly help Parkinson patients if the level of dopamine was restored to normal levels.
    • These compounds, called receptor agonists, would take over the role of dopamine, so no administration of L-DOPA would be needed.
    • The higher the amount of dopamine in the cell through extra L-DOPA, or MOA-B inhibition, the higher the risk of toxication.
    • Given dopamine's role in motor and reinforcement functions, why would dopamine overactivity produce schizophrenic symptoms? One strong possibility is that dopamine release to certain brain regions occurs when you are "attending" to salient events.
    • An overactivity of dopamine at these sites may produce attentional abnormalities, so that stimuli which would normally be ignored are instead considered to be relevant.
    • In addition, substances which increase the release (amphetamine), the synthesis (levodopa) or block the uptake (cocaine, nomifensine, amineptine) of dopamine in the brain inhibit the firing activity of the dopaminergic cells throughout dopamine-mediated mechanisms.
    • The pleasure of dopamine has the power to form both healthy and unhealthy behaviors.
    • The impulse response releases a short pulse of dopamine onto many dendrites, thus broadcasting a rather global reinforcement signal to postsynaptic neurons.
    • Best responses are observed when the time is short between onset of symptoms of shock and initiation of dopamine and volume correction.
    • Lack of dopamine is a cause of parkinson disease which a person looses the ability to initiate controlled movements.
    • Compromise in the flow of dopamine may cause disrupted or incoherent thought as in schizophrenia.
    • A shortage of Dopamine in the frontal lobes may contribute to poor working memory.
    • These substances boost the immune system and provide anti-depressant action by making more of the neurotransmitters serotonin, norepinephrine and dopamine available to the brain.
    • In addition, P5P is necessary for neurotransmitter production, specifically for the production of dopamine, noradrenaline, serotonin, GABA and glutamate.
    • In conjunction with the studies outlined above blood samples will be collected for the measurement of homovanillic acid (HVA), the principal metabolite of dopamine, as well as cortisol and prolactin.
    • Hyperforin increases the effectiveness of norepinephrine, dopamine, L-glutamate, and gamma-amino butyric acid (GABA), as well as serotonin.
    • Circadian rhythms are clearly relevant, particularly with the 24-hour periodicity of dopamine.
    • A mechanism consistent with inactivation by all three groups of inhibitors which proposes that hydroxylation of dopamine by dopamine beta-hydroxylase involves formation of a benzylic radical has been developed.
    • Particularly, we will measure the amount of the chemical dopamine released in the brain as well as the electrical activity during training.
    • A deficiency of dopamine in the brain may explain why some individuals engage in pathological overeating, resulting in severe obesity, according to a study published in this week's Lancet.
    • The mesolimbic system will be referred to a lot in this site, as it is the main focus of dopamine's involvement with drugs.
    • Reviewers' conclusions: There is currently insufficient evidence from randomised controlled trials that the use of dopamine in term infants with suspected perinatal asphyxia improves mortality or long-term neurodevelopmental outcome.
    • Roles of renal dopamine and Kallikrein-Kinin systems in antihypertensive mechanisms of exercise in rats.
    • Continuous adminstration of dopamine alters cellular immunity in chickens.
    • Effects of dopamine on renal receptors for arginine vasopressin.
    • Intracerebroventricular infusion of dopamine and its agonists in rodents and primates.
    • Continuous intracerebroventricular infusion of dopamine and dopamine agonists through a totally implanted drug delivery system in animal models of Parkinson's disease.
    • Spatial distribution of dopamine, methotrexate and antipyrine during continuous intracerebral microperfusion.
    • Behavioural consequences of discrete, chronic infusion of dopamine into the nucleus accumbens of rat.
    • The effects on blood pressure, heart rate and behavior of chronically-administered dopamine into the limbic system.
    • The above therapies are based on the manipulation of endogenous stores of dopamine.
    • Levodopa/Carbidopa (Sinemet) -- Active component is L-isomer of dopamine (ie, L-dopa).
    • Carbidopa is peripheral DOPA hydroxylase inhibitor and by preventing peripheral metabolism increases concentration of dopamine in CNS.
    • If no other factors were at work, MAO would keep the amount of "used" dopamine fairly low.
  • during
  • in
    • Peroutka asks whether it is the increase in dopamine that triggers and maintains a migraine attack.
  • about
  • by
    • This happens as the nervous system tries to make up for less stimulation of the receptors by dopamine itself.
    • There is a delicate balance between these two pathways that is partly maintained by dopamine release from the substantia nigra to the striatum.
    • In this review, we will briefly examine the literature concerning the physiological and behavioural responses caused by dopamine and dopaminergic agents on the dopaminergic neurons of the ventral mesencephalon.
    • Lithium and bupropion antagonise the phasic changes in locomotor activity caused by dopamine infused into the rat nucleus accumbens.
    • Hyperactivity induced by dopamine from rat nucleus accumbens can be modulated by glycine.
    • Increased locomotor activity caused by dopamine infused into the nucleus accumbens of primate brain.
    • Antagonism by lithium of cyclic changes in locomotor activity induced by dopamine infused into rat nucleus accumbens.
  • on
  • to
    • Likewise, the receptors themselves become more sensitive to dopamine.
    • Here overstimulation decreases the number of receptors, and the remaining receptors become less sensitive to dopamine.
    • This could be explained by the fact that the enzyme AADC, which converts L-DOPA to dopamine, is also present in the liver, kidney and many other places in the body.
    • Their method consisted of giving each volunteer subject an injection containing a radiotracer, a radioactive chemical "tag" designed to bind to dopamine receptors in the brain.
    • Besides being converted to dopamine and norepinephrine, they can be converted to other substances that have stimulant and mood-elevating properties.
  • as
    • Vesicular sequestration is important in the regulation of cytoplasmic concentrations of monoamines such as dopamine.
    • John's wort continuing CME - Nutrition Science News, 7/98 - "Surprisingly, the extract was also shown to inhibit the synaptosomal uptake of norepinephrine as well as dopamine with potencies similar to those found with serotonin.
  • for
    • Department of Energy's Brookhaven National Laboratory, obese people have fewer receptors for dopamine, a neurotransmitter that helps produce feelings of satisfaction and pleasure.
    • The role for dopamine in mediating the effects of MDMA has not yet been examined in humans.
    • Department of Energy's Brookhaven National Laboratory, obese people have fewer receptors for dopamine, a neurotransmitter that helps produce feelings of satisfaction and pleasure.
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    • L-DOPA on its turn is converted into dopamine by the enzyme aromatic amino acid decarboxylase (AADC).
    • THE MAIN GOAL of the experiments described in this proposal is to increase our understanding of the interaction between serotonin (5-HT) and dopamine (DA) systems in mediating the subjective, discriminative stimulus, and reinforcing effects of psychostimulant drugs in humans.
  • Compound noun
    • dopamine receptor
      • These drugs bind to dopamine receptors in place of dopamine and directly stimulate those receptors.
      • To compensate for this loss, the body produces more dopamine receptors on other neurons.
      • Sensitization and desensitization do not take place only after long-term understimulation or overstimulation of dopamine receptors.
      • Drugs which act primarily as dopamine receptor agonists or antagonists can serve as important clinical tools.
      • Overall analysis of dopamine receptors in the brain indicate that the striatum, limbic system, and the cortex have more receptors than the rest of the brain, regardless of pathology.
      • To bypass the problem of the side effects of L-DOPA treatment, research started to synthesise compounds that would directly act on the dopamine receptors.
      • While long-term treatment with the available dopamine receptor agonists results to less dyskinesias, the effect is less then that of L-DOPA.
      • There is another reason that favours the research into dopamine receptor agonists.
      • Later, administer a drug that blocks dopamine receptors in the brain (a dopamine antagonist).
      • The upper PET scans show where the radiotracer C-11 raclopride binds to dopamine receptors.
      • To test this hypothesis, the scientists measured the number of dopamine receptors in the brains of ten severely obese individuals and ten normal controls.
      • The PET camera picks up the radioactive signal of the tracer and shows where it is bound to dopamine receptors in the brain.
      • Obese individuals, the scientists found, had fewer dopamine receptors than normal-weight subjects.
      • And within the obese group, the number of dopamine receptors decreased as the subjects' body mass index, an indicator of obesity, increased.
      • "It's possible that obese people have fewer dopamine receptors because their brains are trying to compensate for having chronically high dopamine levels, which are triggered by chronic overeating," says Wang.
      • The dopamine receptors involved in these processes can be separated into the D1 and D2 families.
      • These dopamine receptors are affected by alterations in the neural cell membranes, which could disrupt communication between cells.
      • The brain responds to this receptor blockade by making extra dopamine receptors.
      • To test this hypothesis, the scientists measured the number of dopamine receptors in the brains of ten severely obese individuals and ten normal controls.
      • Their method consisted of giving each volunteer subject an injection containing a radiotracer, a radioactive chemical "tag" designed to bind to dopamine receptors in the brain.
      • The PET camera picks up the radioactive signal of the tracer and shows where it is bound to dopamine receptors in the brain.
      • Obese individuals, the scientists found, had fewer dopamine receptors than normal-weight subjects.
      • And within the obese group, the number of dopamine receptors decreased as the subjects' body mass index, an indicator of obesity, increased.
      • "It's possible that obese people have fewer dopamine receptors because their brains are trying to compensate for having chronically high dopamine levels, which are triggered by chronic overeating," says Wang.
      • It has been observed previously that in humans drugs such as certain anti-psychotic medications that block dopamine receptors increase appetite and result in significant weight gain, whereas drugs such as methamphetamine that increase brain dopamine levels diminish appetite.
      • In both groups, dopamine receptors in the brain were measured with positron emission tomography (PET) scans and other tests.
      • Wang cautions that this study "can not determine if the brain changes in the obese individuals are a consequence or cause of obesity." He says additional research is needed to evaluate dopamine receptor levels before and after successful weight loss.
      • The presence of dopamine receptors in the stomach helps explain the accompanying decrease in gastric tone, peristalsis, emptying, and disrupted gastroduodenal coordination.
      • Antagonism by ketotifen of changes in dopamine receptor sensitivity in the rat brain.
      • The continuity of dopamine receptor antagonism can dictate the long-term behavioural consequences of a mesolimibic infusion of dopamine.
      • A comparison of the behavioural consequences of chronic stimulation of dopamine receptors in the nucleus accumbens of rat brain effected by a continuous infusion or by single daily injections.
      • Five subtypes of dopamine receptor have been cloned.
      • The role of other dopamine receptor subtypes is currently unclear.Drug Name
    • dopamine level
      • However, drugs can affect dopamine levels.
      • Amphetamine also increases dopamine levels.
      • However, the is much debate in the scientific community as to the exact mechanism by which altered dopamine levels, especially in the prefrontal cortex, striatum, and limbic system, produce schizophrenia.
      • Subsequent studies showed that dopamine levels in the striatum were drastically reduced.
      • Another way to increase dopamine levels is to block the enzyme MOA-B that is converting dopamine to DOPAC.
      • Treatment that aims to increase dopamine levels turns out not stop the further deterioration of dopaminergic cells, and hence does not work well in the long term.
      • Cocaine and amphetamine both elevate dopamine levels in the brain.
      • A number of psychiatric disorders, particularly schizophrenia, Parkinson¡¯s disease, and mood disorders, are attributed to imbalances in dopamine levels.
      • Elevation of dopamine levels often leads to an improvement in mood, alertness, and sex drive, and perhaps even an enhancement in verbal fluency and creativity.
      • Unfortunately, many of the drugs that have been shown to alter dopamine levels are highly addictive.
      • Moreover, recent evidence suggests that increases in cytoplasmic dopamine levels, perhaps attributable to changes in vesicular monoamine transporter function, contribute to methamphetamine-induced dopaminergic deficits.
      • Otto Kuchel, hypothesized that these patients might have such high dopamine levels that dopaminergic depressor effects would be manifest.
      • It's the time of day when serotonin and dopamine levels, which regulate mood, sleep and emotion, naturally dip.
      • One approach has been to increase internal dopamine levels by molecules that occur naturally in the body, such as nicotinamide adenine dinucleotide (NADH) and cytidinediphosphocholine (CDP-choline).
      • Unfortunately, many of the drugs that have been shown to alter dopamine levels are highly addictive.
      • To find out, Phillips et al.4 measured dopamine levels by implanting a carbon-fibre electrode into the nucleus accumbens of rats that had been trained to press a lever to receive a cocaine injection.
      • In animals that had learned to associate the audiovisual cue with cocaine, the cue itself caused a rapid increase in dopamine levels for several seconds (Fig.
      • Previous studies detected prolonged increases in dopamine levels that lasted for several minutes following a drug reward.
    • dopamine neuron
      • Indirect agonists are not very effective in treating the disease since they depend on the presence of dopamine neurons.
      • This form of MAO, found in dopamine neurons, acts on substances in the neuron other than dopamine.
      • Parkinson's Disease (PD) is accompanied by a selective destruction of dopamine neurons in the substantia nigra of the midbrain which send their axon terminals to the striatum which is involved in motor control.
      • Of course, dopamine neurons did not evolve to mediate cocaine reward, but presumably evolved to mediate the reinforcing effects of natural rewards, such as food, water and sex.
      • Dopamine neurons projecting to the striatum are implicated in motor functions.
      • A loss of these "nigrostriatal" dopamine neurons is the cause of Parkinson's disease (tremors, rigid movements, difficulty initiating movements).
      • Dopamine neurons of the mesolimbic and nigrostriatal systems respond to reward events.
      • Dopamine neurons in the ventral tegmental area (VTA) are widely believed to provide a reward signal.
      • Most dopamine neurons show phasic activations after primary liquid and food rewards and conditioned, reward-predicting visual and auditory stimuli.
      • Thus dopamine neurons label environmental stimuli with appetitive value, predict and detect rewards and signal alerting and motivating events.
      • By failing to discriminate between different rewards, dopamine neurons appear to emit an alerting message about the surprising presence or absence of rewards.
      • Dopamine neurons are activated by rewarding events that are better than predicted, remain uninfluenced by events that are as good as predicted, and are depressed by events that are worse than predicted.
    • dopamine antagonists
      • Dopamine antagonists are traditionally used to treat schizophrenia and related mental disorders.
      • For example, long-term treatment with dopamine antagonists increases the number of dopamine receptors.
      • As you might imagine, a rat under the influence of a dopamine antagonist drug is likely to show some impairment in its ability to perform operant responses, like lever-pressing.
      • Almost all "antipsychotic" drugs prescribed for schizophrenics are dopamine antagonist drugs.
      • Individuals who overdose on amphetamine and cocaine (dopamine agonist drugs) often develop psychotic symptoms (hallucinations/delusions) which are indistinguishable from those of schizophrenics.
      • The traditional dopamine/reward view arose largely from observations of the pattern of reinforced responding in animals under the influence of dopamine antagonist drugs.
      • Animals under the influence of dopamine antagonist drugs show reduced rates of responding for natural rewards such as food and water.
      • This study introduces a methodology for asking whether dopamine antagonists disrupt reinforcement, without the motor confound that usually clouds such investigations.
      • This response-reinstatement is blocked in animals under the influence of a dopamine antagonist drug during the reinforced trial.
      • Peroutka, MD, PhD, Spectra Biomedical Inc, Menlo Park, Calif, advocates using dopamine antagonists with serotonin agonists in treating migraine.
      • Open-label emergency room data suggest that injections of dopamine antagonists relieve acute migraine attacks.
    • dopamine infusion
      • Bilateral hypothalamic dopamine infusion in male Zucker rat suppresses feeding due to reduced meal size.
      • Dopamine distribution and behavioral alterations resulting from dopamine infusion into the brain of the lesioned rat.
      • Chronic intrastriatal dopamine infusions in rats with unilateral lesions of the substantia nigra.
      • Behavioral effects of continous intrastriatal dopamine infusions in animals with and without unilateral lesions of the substantia nigra.
      • Chronic effects of a brief period of dopamine infusion into the nucleus accumbens.
      • The behavioural and biochemical consequences of dopamine infusion into the frontal cortex of rat brain.
      • Long-term consequences of antagonism by neuroleptics of behavioural events occurring during mesolimbic dopamine infusion.
      • Locomotor hyperactivity caused by dopamine infusion into the nucleus accumbens of rat brain: specificity of action.
      • Numbers of striatal (3H) NPA binding sites change to compensate for consequences of chronic mesolimbic dopamine infusion.
      • Influence of medial raphe nucleus lesions on behavioural responding to dopamine infusion into the rat amygdala.
    • dopamine agonists
      • Some drugs are known as dopamine agonists.
      • Some dopamine agonists are currently used to treat Parkinson's disease.
      • In contrast to dopamine agonists, dopamine antagonists are drugs that bind but don't stimulate dopamine receptors.
      • Dostinex is a dopamine agonists, and it works by enhancing desire and orgasm, not just erections, as it is the case with Viagra.
      • Reports of edema as a side effect of other dopamine-agonists (bromocriptine, pergolide, ropinerole) have been inconsistent.
      • Many doctors who treat Parkinson people are unaware that swelling of the legs can, occasionally, be a complication of dopamine agonists.
      • Bromocriptine, a dopamine agonist, produces a predictable dose-related series of clinical signs.
      • Chronic enhancement of dopamine agonist action after intra-accumbens dopamine infusion.
    • Dopamine-beta-hydroxylase
      • The apoform of neurocuprein, the copper protein from brain and chromaffin granules, was found to be a potent inhibitor of the hydroxylating activity of dopamine beta-monooxygenase, whereas the holoform of neurocuprein has no effect on the activity of the enzyme.
      • Peptidylglycine alpha-amidating enzyme (alpha-AE) and dopamine beta-monooxygenase (D beta M), two copper-dependent monooxygenases that have catalytic and structural similarities, are irreversibly inactivated by sodium sulfite.
      • Dopamine-beta-hydroxylase (DBH), the enzyme that catalyzes the conversion of dopamine to norepinephrine, remains the topic of many unanswered questions.
      • The carbon monoxide complex of ascorbate-reduced dopamine beta-hydroxylase has been prepared identifying the CO-binding site as the O2-binding site.
      • The structure of the copper sites in oxidized and reduced dopamine beta-hydroxylase has been studied by extended x-ray absorption fine structure spectroscopy.
      • A comparison of human dopamine beta-hydroxylase (EC 1.14.17.1) with bovine peptide C-terminal alpha-amidating enzyme (EC 1.14.17.3), revealed a 28% identity extending throughout a common catalytic domain of approximately 270 residues.
      • Mechanism-based inhibitors for dopamine beta-hydroxylase have been used as probes of the mechanism of catalysis.
    • dopamine system
      • A person with schizophrenia may have an overactive dopamine system.
      • It is also well established that the euphoric and rewarding responses evoked by drugs of addiction, such as amphetamine and cocaine, are mediated by central dopamine systems.
      • "The thinking is that addiction, craving, [and] even pleasure comes from the modulation of the dopamine system," Caron said.
      • "Nicotine, alcohol, marijuana, even caffeine?which act on different targets? may all have common reward or reinforcing effects through the dopamine system." Caron next plans to see if his knockout mice will self-administer addictive substances.
      • Behavioral and biochemical consequences of persistent overstimulation of mesolimbic dopamine systems in the rat.
      • Examples include transgenic animals containing knockouts of transferrin gene, or manipulations of dopamine system genes.
    • dopamine function
      • Cocaine and other drugs of abuse can alter dopamine function.
      • Other investigators are more conservative, and point out that most of our knowledge about dopamine function comes from studies in rats.
      • Modulation of dopamine function by glycine in the nucleus accumbens of the brain of the rat.
      • Laterality of dopamine function and neuroleptic action in the amygdala in the rat.
      • What's missing, crucially, is vigorous and prolonged stimulation of meso (cortico) limbic dopamine function.
    • dopamine activity
      • Imbalanced dopamine activity can cause brain dysfunction and disease.
      • Investigators have suggested that dopamine activity may underlie the ability of conditioned incentive stimuli (events that have previously been associated with primary rewards) to activate and motivate behavior.
      • This study asked whether stimuli that have previously been paired with reward, maintain their motivational/arousing (conditioned incentive) properties even when brain dopamine activity has been disrupted.
      • A decline in dopamine activity in the brain is linked to cognitive (learning and memory) and movement problems in those with Parkinson's disease.
    • dopamine release
      • Schultz8 found that such cues acquire the ability to activate dopamine release in the brain as they become associated with rewards through pavlovian learning.
      • It is as if the brain reserves dopamine release for the most important events, signalling the occurrence of unexpected, novel rewards when learning is important, but not when those rewards were already anticipated thanks to a predictive cue.
      • Reward-predicting environmental cues, then, can stimulate dopamine release ? but it has been difficult to prove whether such cues actually 'use' dopamine to trigger reward-seeking behaviour.
      • Definitive proof would require accurate subsecond measurements of dopamine release to determine whether dopamine pulses precede the initiation of reward-seeking behaviour.
    • dopamine hydrochloride
      • Dopamine hydrochloride is a white to off-white crystalline powder, which may have a slight odor of hydrochloric acid.
      • Dopamine hydrochloride injection is a clear, practically colorless, sterile, pyrogen-free, aqueous solution of dopamine HCl for intravenous infusion after dilution.
      • Each milliliter of the 80 mg/mL preparation contains 80 mg of dopamine hydrochloride (equivalent to 64.62 mg of dopamine base).
    • dopamine transporter
      • Hyperlocomotion and indifference to cocaine and amphetamine in mice lacking the dopamine transporter.
      • Jeon BS, Jeong JM, Park SS: Dopamine transporter density measured by [123I]beta-CIT single-photon emission computed tomography is normal in dopa-responsive dystonia.
      • Good methods, which use the dopamine transporter to label the pathways, are now available.
    • dopamine pathway
      • Dopamine pathways need to be re-explored because previous studies did not necessarily use good methods.
      • The brain and the spinal cord, especially descending dopamine pathways, should be explored.
      • Particular attention should be paid to dopamine pathways, but opiate and orexin pathways should also be considered.
    • X + noun ±âŸ
      • One of the most famous and most debatable is the dopamine hypothesis.
      • The major support and refutation of the dopamine hypothesis has come from the examination of dopamine receptors in these regions of the brain.
      • When these neurons start to disappear, the normal rate of dopamine production decreases.
      • Dopamine production increases through the night with each cycle of rapid eye movement (REM) sleep.
      • Some investigators believe that when you experience pleasurable events, you can thank dopamine release in the nucleus accumbens for the reward experience.
      • "In animal studies conducted elsewhere, exercise has been found to increase dopamine release and to raise the number of dopamine receptors," Volkow says.
      • The results provide evidence for a dopamine involvement in food reinforcement.
      • The methodology introduced in this paper has subsequently been employed to investigate dopamine involvement in the reinforcing properties of water, cocaine, amphetamine, and heroin.
      • "In animal studies conducted elsewhere, exercise has been found to increase dopamine release and to raise the number of dopamine receptors," Volkow says.
      • Stimulation of dopamine release with the molecule amantadine may have clinical application for Parkinson's patients.
      • By signaling rewards according to a prediction error, dopamine responses have the formal characteristics of a teaching signal postulated by reinforcement learning theories.
      • Dopamine responses transfer during learning from primary rewards to reward-predicting stimuli.
      • Drugs abused by humans preferentially increase synaptic dopmaine concentrations in the mesolimbic dopamine system of freely moving rats.
      • With increased dopamine concentration, these oscillations increase in frequency.
      • Dopamine (DA) overflow in the mouse nucleus accumbens during intracranial self-stimulation (ICSS) of the median forebrain bundle was estimated by chronoamperometry with removable carbon fibre electrodes.
      • The CR schedule induced a high rate nose-poking and tonic increase in dopamine overflow, which became decreased following the first periods of self-stimulations.
      • Pathophysiology: DRD is characterized by striatal dopamine deficiency with preservation of nigrostriatal terminals.
      • Causes: Patients with DRD have selective nigrostriatal dopamine deficiency without neuronal loss caused by genetic defects in dopamine synthesis.
      • These findings suggest that naturally evoked dopamine pulses are involved in both triggering and pursuit of reward-seeking behaviour, and that environmental cues (here, the test chamber or the audiovisual cue) use this mechanism to prime such behaviour.
      • Phillips et al.4 suggest that subsecond dopamine pulses are released only when drug-induced dopamine levels fall below a certain threshold.
      • The dopamine theory of depression was studied by assessing the effect of antidepressant drugs on uptake of dopamine, noradrenaline, and serotonin in synaptosomes from rat brain.
      • The results suggest that a reversible inhibition of dopamine uptake occurs following chronic low dose selegiline treatment in vivo which may be mediated by an increase in endogenous MAO-B substrates such as 2-phenylethylamine, rather than by the inhibitor molecule or its metabolites.
      • But exercise, which has other obvious benefits in weight control, is another way obese subjects might be able to stimulate their dopamine pleasure and satisfaction circuits, the researchers suggest.
      • The dopamine diet plan will help you to become addicted to eating healthy.
      • There are two small problems associated with our Dopamine Reduction Guide: the problems with dieting and its poor health return.
      • Changing the action of MAO can help us treat diseases that involve dopamine transmission.
      • Dopamine research has enhanced scientists' understanding of how diseases and addictions originate and develop.
      • It was discovered that when dopamine supply is abnormally low, Parkinson's symptoms start to appear.
      • The synthesised dopamine molecules in the presynaptic terminal are then taken up by synaptic vesicles.
      • Therefore, if the rat under the influence of a dopamine-blocking drug stops lever-pressing for food, it is difficult to determine whether this is because the food has lost its reinforcing propertes or whether it is because it is now more difficult to perform the operant response.
      • Dopamine and Schizophrenia Another issue in the dopamine story is that dopamine is implicated in schizophrenia.
      • This paper demonstrates that dopamine disruptions do not reduce thirst.
      • Reductions in water-reinforced behavior seen in dopamine-disrupted animals (Ettenberg and Horvitz 1990), then, cannot be accounted for by reductions in the animal's primary motivational state.
      • Dopamine HCl is sensitive to alkalies, iron salts, and oxidizing agents.
      • The dopamine reward signal is supplemented by activity in neurons in striatum, frontal cortex, and amygdala, which process specific reward information but do not emit a global reward prediction error signal.
      • Most deficits following dopamine-depleting lesions are not easily explained by a defective reward signal but may reflect the absence of a general enabling function of tonic levels of extracellular dopamine.
      • Enhanced responsiveness of post-synaptic dopamine D2/D3 receptors is crucial to long-term emotional well-being.
      • A 20-second oscillation occurs in the firing rates in dopamine-sensitive neurons in basal ganglia.
      • What is the extent to which the dopamine connection is in common among the disorders? So far, the only thing in common is that the patients respond to drugs that act on dopamine.
      • Chronic implants of chromaffin tissue into the dopamine-denervated striatum.
      • Parkinson's disease has been treated successfully with the dopamine precursor l-DOPA, which, unlike dopamine, can cross the blood-brain barrier.
      • The cause of Parkinson's disease is unknown, although some clues were offered with the discovery of a selective dopamine toxicity produced by the synthetic compound 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP).
      • The variations in presentation (eg, spasmodic torticollis, oromandibular dystonia, writer’s cramp) should be differentiated from idiopathic (ie, dopamine-nonresponsive) focal dystonias.
      • Regular outpatient follow-up is required to assess the efficacy of treatment and to adjust the dopamine dose accordingly.
      • Dopamine D(1)/D(5) receptor antagonism has been shown to block the euphoric and stimulatory effects of cocaine in humans and rats.
      • But what are the neurochemical signals that actually 'trigger' reward-seeking behaviour as a result of dopamine-mediated reinforcement? Obviously, these signals must occur before, and not after, the reward is received.
      • As a rat chases its tail, so drug addicts may suffer a similar vicious circle of priming and reward controlled by these dopamine signals.
      • We investigated the effect of pretreatment with the dopamine D(2) antagonist haloperidol (1.4 mg i.v.) on psychological and physiological responses to MDMA (1.5 mg/kg p.o.) in 14 healthy volunteers using a double-blind placebo-controlled within-subject design.
      • The purpose of this study was to evaluate the neuromodulator properties of PEA on dopamine (DA) release as reflected by 3MT steady-state concentrations.
      • More than a century later, one believes that the cause of the disease is a dopamine deficiency in the basal ganglia of the brain.
    • ±âŸ noun + X
      • It is believed that the powerfully-reinforcing and rewarding properties of cocaine and amphetamine are due to this increase in brain dopamine activity.
      • Reductions in brain dopamine activity produce reductions in movement.
      • Modulating brain dopamine and 5-HT in migraineurs mirrors the approach used in treating hypertension with blood pressure and cholesterol lowering agents.
      • Indeed, VTA dopamine neurons respond to reward events, like food or conditioned stimuli signalling food delivery.
      • However, this paper demonstrates that the VTA dopamine neurons also respond to salient sensory events which are not rewarding or reward-related.
      • The effects of lesions, receptor blocking, electrical self-stimulation, and drugs of abuse suggest that midbrain dopamine systems are involved in processing reward information and learning approach behavior.
      • The amino acid tyrosine and the phytonutrient Mucuna pruriens increases the level of the neurotransmitter dopamine.
      • State-of-the-art technology has allowed pulses of the neurotransmitter dopamine to be measured on a subsecond timescale in the brains of rats.
      • Serotonin-mediated increase in prefrontal cortex dopamine release: Pharmacological characterization.
      • The copper-containing monooxygenase dopamine beta-hydroxylase catalyzes the hydroxylation of dopamine at the benzylic position to form norepinephrine.
      • This study compared low dose dopamine at 2.5 mcg/kg/min with placebo (dextrose in water).
      • The present study was carried out to determine whether this effect of selegiline could be the result of an inhibition of the high-affinity dopamine neuronal transport process.
      • Uptake of [3H]-dopamine was determined in synaptosomes from selegiline-treated animals.
      • The increase in DAT expression, and attenuation of amphetamine-induced dopamine release, were not accompanied by a change in [3H]-dopamine uptake in synaptosomes of selegiline-treated animals.
      • Characteristics of rat kidney dopamine receptors and the effects of renal denervation and dopamine infusion on these receptors.
      • Chronic intra-accumbens dopamine: behavioural consequences of continuous infusion or single daily injections.
      • Arachidonoyl dopamine (AA-DA) is one of several 'hybrid' analogs which incorporate components of both the anandamide and capsaicin molecules.1 AA-DA is the amide of the neurotransmitter dopamine and arachidonic acid.
      • The midbrain dopamine system has generated intensive research, because they have been implicated in many disorders : thought and affective disorders such as schizophrenia, manic-depressive illness, tardive dyskinesia or degenerative disorders such as Parkinson's disease and Huntington's chorea.
      • But drug-seeking behaviour ceases during these large, post-injection dopamine increases.
  • ±âŸ
    • dopaminergic
      • From a therapeutic point of view, the above-mentioned agonists are used for treating Parkinson's disease, acting over DA 2 dopaminergic receptors of the nigrostriatal system.
      • Bromocriptine and the other dopaminergic agonists mentioned act over DA 2 receptors of the tuberoinfundibular system, inhibiting prolactin release and decreasing hyperprolactinemia and tumor size.
      • Much of the research points to alterations in dopaminergic pathways.
      • Prototypic dopaminergic terminal with cycle of synthesis, storage, release and removal of dopamine.
      • Because the basal ganglia contains most of the dopaminergic neurons of the brain, these observations suggested that the dopaminergic pathway between the striatum and substantia nigra are degenerated in PD patients.
      • It was found out that these animals all suffered from a loss of dopaminergic cells in substantia nigra pars compacta, and a subsequent reduction in the levels of dopamine in the striatum.
      • The hypothesis has been put forward that long term treatment with L-DOPA accelerates the degeneration of dopaminergic cells.
      • Several lines of evidence suggest that a degeneration of dopaminergic cells in the substantia nigra produces the symptoms of Parkinson's disease.
      • The dopaminergic neurons of the substantia nigra pars compacta and ventral tegmental area play a crucial role in regulating movement and cognition respectively.
      • On the other hand, a hyperactivity of the dopaminergic transmission in the brain induces dyskinesia, dystonia and psychosis.
      • Electrophysiological experiments which study the activity of single dopaminergic neurons in the ventral mesencephalon have shown that dopamine and dopaminergic drugs reduce the firing frequency of these cells.
      • Results are consistent with a partial dopaminergic mediation of the euphoriant effects of MDMA.
      • The dopaminergic system in the brain seems to play an important role in the regulation of sexual behaviour.
      • He has a state-of-the-art approach to improving patients' sexual function, and is aware of the beneficial effect of dopaminergic drugs such as apomorphine and bromocriptine.
      • And new anti-Parkinsonian and anti-Alzheimer's agents, notably roxindole and pramipexole, owe their potential role as fast-acting antidepressants to their dopaminergic action.
      • "Dopaminergic" (and opioid) agents, by contrast, are suspect.
      • A dopaminergic system may play a role in some forms of motor learning.
      • Des-enkephalin-y-endorphin blocks dopaminergic hyperactivity in rats and marmosets.
      • Effects of the 5-HT3 receptor antagonist, GR38032F, on raised dopaminergic activity in the mesolimbic system of the rat and marmoset brain.
      • Dopaminergic modulation of aldosterone secretion in the rat.
      • The next neurotransmitter system to be covered will be the dopaminergic system.
      • One of the most important CNS dopaminergic pathways projects from the substantia nigra pars compacta to the neostriatum.
      • An important interaction exists between the cholinergic and dopaminergic systems in the striatum.
      • In healthy individuals, the enzyme activity in the nigrostriatal dopaminergic neurons shows variation with circadian rhythm and age.
      • The activity of these dopaminergic neurons also has circadian variation.
      • Drug Category: Dopaminergic agents -- In order for a dopamine agonist to offer clinical benefit, it must stimulate D2 receptors.
      • The dopaminergic cells in the mesencephalon form a continuum that includes the cell-rich substantia nigra pars compacta (group A9), a medially located aggregation of cells (A10) primarly in the ventral tegmental area and cell group A8 in the retrorubal area, which is contiguous with the caudal portion of the substantia nigra pars compacta.
      • DA neurons of the pars compacta are known as the A9 dopaminergic cell group and extend posteriorly into the retrorubral field composed of A8 dopaminergic cell group.
      • Dopaminergic fibers can be visualized by E14.5 and proceed to innervate the cortex, caudate-putamen and other terminal fields throughout prenatal and early postnatal development.
      • One set of eph receptor-ligand pair (EphB1 and Ephrin-B2) are expressed in complementary fashion in the midbrain dopaminergic system.
      • Also recent data display several collapsins (mainly SemB and F) in the striatum at stages correlating with the development of the midbrain dopaminergic system.
    • 6-hydroxydopamine
      • A continuous striatal infusion of 6-hydroxydopamine produces a terminal axotomy and delayed behavioral effects.
      • Time course study of changes in the activity of rats during intraventricular infusion of 6-hydroxydopamine, haloperidol and sulpiride: a study of the relationship between an origin of the negative symptoms in schizophrenia and catecholamines.
      • Increased Beta -adrenoceptor density after 6-hydroxydopamine pretreatment in rat colon and lung.
      • The neurotoxic actions of 6-hydroxydopamine infused into the rat substantia nigra.
      • GM1 ganglioside enhances regrowth of noradrenaline nerve terminals in rat cerebral cortex lesioned by the neurotoxin 6-hydroxydopamine.
      • The stability of 6-hydroxydopamine under minipump conditions.
      • Stability of 6-hydroxydopamine under minipump conditions.
      • Effects of intracortical infusion of 6-Hydroxydopamine on the response of kitten visual cortex to monocular deprivation.
      • Effects of 6-hydroxydopamine on visual deprivation in the kitten striate cortex.
      • Visual cortical plasticity: deficit after acute, but not chronic, noradrenergic denervation with 6-hydroxydopamine.
      • Regrowth of central catecholaminergic fibers in cat visual cortex following localized lesion with 6-hydroxydopamine.
      • Effect of 6-hydroxydopamine on plasticity of direction selective cells in visual cortex.
      • Effects of intracortical infusion of 6-hydroxydopamine on monocular and directional deprivation.
      • Cortical recovery from effects of monocular deprivation: acceleration with norepinephrine and suppression with 6-hydroxydopamine.
      • Catecholaminergic terminals in kitten visual cortex: The normal distribution and its changes following the local microperfusion of 6-hydroxydopamine.
      • Local perfusion of 6-hydroxy-dopamine prevents recovery of visual cortical cells from the effects of monocular occlusion in kittens.
  • ±âŸ inflections
    • N-acyl-dopamines: novel synthetic CB1 cannabinoid-receptor ligands and inhibitors of anandamide inactivation with cannabimimetic activity in vitro and in vivo.
    • There are several agonists of dopamine-2 (DA 2 ) dopaminergic receptors, such as bromocriptine, pergolide, lisuride, quinpirole, and carmoxirole, which inhibit norepinephrine release and produce a decrease in arterial blood pressure; in some cases, bromocriptine and pergolide also reduce heart rate.
  • °íÀ¯¸í»ç
    • Team Dopamine, an interdisciplinary group of senior scientists working at The University of North Carolina at Chapel Hill and Purdue University, share a common research interest in the mechanisms of dopamine neurotransmission.
    • I've been screaming into the ether, "plastering myself all over the internet" as one stalker put it,for two solid years now, here, as the Dopamine Junkie.
    • This year Dopamine Junkie held on to friendships with readers/ex-lovers like the Young Pyromaniac and the Connoisseur.
    • I wonder if his relationships are as riddled with scar tissue as mine are.This year, Dopamine Junkie became the Little One, who became Domina Jane Die.This year, Dopamine Junkie collected a passel of submissives,who have mostly either failed or been dismissed.A few real connections were made however.King of BeastsMy best pet could not afford to give me extravagant gifts.This pet was not only equipped with delicious masochistic tendenciesbut also a submissive heart of a true lion beast.We met first at my home.
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