Dopaminergic function

Di Matteo V., Cacchio M., Di Giulio C., Esposito E. (2002). Role of serotonin (2C) receptors in the control of brain dopaminergic function. Pharmacol. Biochem. Behav. 71, 727-34. 

Smolka, M.N., Budde, H., Karow, A.C., Schmidt, L.G. Neuroendocrinological and neuropsychological correlates of dopaminergic function in nicotine dependence. Psychopharmacology. 175 374, 2004. 

Cass, W.A., Manning, M.W. Recovery of presynaptic dopaminergic functioning in rats treated with neurotoxic doses of methamphetamine. J. Neurosci. 19 7653, 1999. 

Wood, P. L., Scotland, M., Richard, J. W., and Rackham, A. (1980) Actions of mu, kappa, sigma, delta and agonist/antagonist opiates on striatal dopaminergic function. J. Pharmacol. Exp. Then, 215 697-703. 

Dopamine A few studies have examined the dopaminergic effects of LSD. The affinity of LSD for D2 receptors is similar to its affinity for 5-HT2 sites, and it has a slightly lower affininty for D1 receptors (Watts et al. 1995). LSD has partial agonist effects at D2 receptors as seen in the inhibition of prolactin release (Giacomelli et al. 1998). Neuroleptic drugs are also used clinically to terminate an LSD experience. Thus, the effects of LSD on dopaminergic function may contribute to its hallucinogeinc effects. 

Becker JB. 1999. Gender differences in dopaminergic function in striatum and nucleus accumbens. Pharmacol Biochem Behav 64(4) 803-812. 

Results of studies on animals have indicated that styrene treatment (0.5 g per kg body weight) alters dopaminergic function in some brain regions that are important in the initiation and control of movement. However, the deficits in motor function resulting from styrene exposure were not permanent and the functions returned to control levels after cessation of such treatment (Chakrabarti, 2000). 

Balfour Dl, Wright AE, et al (2000) The putative role of extra-synaptic mesolimbic dopamine in the neurobiology of nicotine dependence. Behav Brain Res 113(l-2) 73-83 Beatty WW (1979) Gonadal hormones and sex differences in nonreproductive behaviors in rodents organizational and activational influences. Horm Behav 12(2) 112-163 Becker JB (1999) Gender differences in dopaminergic function in striatum and nucleus accumbens. Pharmacol Biochem Behav 64(4) 803-812... 

With regard to the specific action of antidepressants on the dopaminergic system, there is evidence that buproprion (not marketed in most countries in Western Europe as an antidepressant but available in North America), amineptine and nomifensin (withdrawn because of the rare occurrence of haemolysis) owed their antidepressant efficacy to their ability to increase central dopaminergic function. There are also open label studies to suggest... 

D Amato, F. and Cabib, S. (1987). Chronic exposure to a novel odor increases pups vocalizations, maternal care, and alters dopaminergic functions in developing mice. Behavioral and Neural Biology 48,197-205. 

Pharmacotherapeutic measures are aimed at restoring dopaminergic function or suppressing choUnergic hyperactivity. 

The specific etiology of psychotic disorders has not currently been sufficiently investigated. It is believed, however, that the initial cause of psychotic behavior may originate from an imbalance of dopaminergic functions in the CNS. Many researchers adhere to the opinion that a large increase of dopamine activity in specific regions of the CNS is the cause of abnormal behavior. 

Table 2. A prehminary evaluation of the relationship between dopaminergic function and impaired consciousness in dementia with Lewy bodies.

Rodent models thus provide opportunities to explore the relationship between dopaminergic function, attention and consciousness. Based upon the well designed study of Granon et al. (2000) showing a clear improvement of attentional performance after the infusion of a D1 agonist into the prefrontal cortex, further study of cortical arousal and variability of reaction times in these models may provide important information. The preliminary data indicating that D2 receptor antagonists may increase cortical arousal (Sebban et al., 1999) is contrary to expectation and requires confirmation... 

The development of PET as a research tool and diagnostic procedure has had particularly valuable CNS applications. Metabolic studies using [ F]-2-fluoro-2-dexoy glucose ([ F]-FDG), quantitation of regional dopaminergic function with... 

Deprenyl. Deprenyl, a selective monoamine oxidase B inhibitor that enhances dopaminergic function, is used in the treatment of Parkinson s disease. An open-label study (Jankovic et al., 1994) suggested that deprenyl could be effective for the treatment of ADHD in children with TS. A placebo-controlled crossover study (Feigin et al., 1996) of 24 subjects with ADHD and a tic disorder found that deprenyl was safe and effective at doses ranging from 5 to 10 mg/day. Only one subject showed an increase in tics. Interpretation of these results, however, is hampered by the clear evidence of an order effect. Subjects who received active drug first showed a 37% improvement in ADHD... 

Dwoskin LP, Jewell AL, Cassis LA DuP 753, a non-peptide angiotensin II-l receptor antagonist, alters dopaminergic function in rat striatum. Arch Pharmacol 345 153-159, 1992... 

Amantadine, an antiviral agent, was by chance found to have antiparkinsonism properties. Its mode of action in parkinsonism is unclear, but it may potentiate dopaminergic function by influencing the synthesis, release, or reuptake of dopamine. It has been reported to antagonize the effects of adenosine at adenosine 2 receptors, which are receptors that may inhibit D2 receptor function. Release of catecholamines from peripheral stores has also been documented. 

Thus, it may be that decreases in 5HT tonic inhibitory influences on DA neurons could lead to increased dopaminergic function due to the functional connections between DA and 5HT neurons in the basal ganglia. Thus, OCD patients with a history of Tourette syndrome may represent a subtype of the disorder in which two neurotransmitters and the balance between them are involved in the pathophysiology of their symptoms. 

Schizophrenia is currently viewed as a complex, at least in part neurodevelomental disorder of unknown etiology. A number of structural changes in schizophrenic brains have been described, and changes in dopaminergic functions are associated with many other neurotransmitter and receptor changes54 60 7. Reduced of histamine H, receptor binding in... 

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