Cocaine psychostimulant

Both psychostimulants D-amphetamine and cocaine elevate extracellular dopamine concentrations in the terminal region of midbrain dopamine neurons,... 

Cocaine and desipramine inhibit the reuptake of monoamine neurotransmitters whereas amphetamine, which is a phenylalkylamine - similar in structure to the catecholamines, see Fig. 4 - competes for uptake and more importantly, evokes efflux of the monoamine neurotransmitters. All of them exert antidepressant effects. Cocaine and amphetamine are addictive whereas tricyclic antidepressants and their modern successors are not. The corollaty of the addictive properties is interference with DAT activity. Blockade of DAT by cocaine or efflux elicited by amphetamine produces a psychostimulant effect despite the different mechanisms even the experienced individual can hardly discern their actions. Because of the risk associated with inhibiting DAT mediated dopamine clearance the antidepressant effects of psychostimulants has not been exploited. 

Psychostimulants. Table 2 Influence of the psychostimulants amphetamine, cocaine, and methylphenidate on the different biogene amines... 

Sevarino KA, Oliveto A, Kosten TR Neurobiological adaptations to psychostimulants and opiates as a basis of treatment development. Ann N Y Acad Sci 909 51 —87,2000 Silberman EK, Reus VI, Jimerson DC, et al Heterogeneity of amphetamine response in depressed patients. AmJ Psychiatry 138 1302—1307, 1981 Sofuoglu M, Brown S, Babb DA, et al Depressive symptoms modulate the subjective and physiological response to cocaine in humans. Drug Alcohol Depend 63 131-137, 2001... 

To summarize the data in table 1, neither MDMA nor MBDB has hallu-cinogen-like discriminative stimulus properties. Symmetrical transfer of the MDMA and MBDB stimulus indicates that their primary discriminative stimulus effects are very similar. For both MDMA and MBDB, there is enantioselectivity for the S isomer, with about a twofold eudismic ratio. Finally, the substitution of (- )-amphetamine and cocaine in MDMA-trained rats may indicate that MDMA has some psychostimulant-like properties, while hffiDB seems to lack this activity. 

Investigation of the neurochemical substrates for the psychostimulant effects of MDMA suggests a role for the mesolimbic dopamine system. Destruction of dopamine terminal fields in the nucleus accumbens significantly attenuated the locomotor activation produced by MDMA. A similar blockade of amphetamine-induced locomotor hyperactivity is known and was observed following amphetamine injection in these same rats. Such results support the hypothesis that at least one component of MDMA-induced hyperactivity is dopamine mediated and suggest that mesolimbic dopamine specifically is the critical substrate. In this way, MDMA resembles other classical psychostimulants like amphetamine and cocaine. Interestingly, evidence for functional cross-sensitization was suggested in the study in which an injection of amphetamine followed MDMA injection. 

One of the most common psychostimulants, cocaine, is derived from the coca plant (Erythroxylon coca) and has a long history as a stimulant. It has been used for centuries in Bolivia and Peru as a tonic and other preparations to alleviate fatigue (Siegel 1985 Hill et al. 1977). 

Cocaine A potent psychostimulant with local anaesthetic properties extracted from the South American plant Erythroxylon coca. 

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