Cocaine psychomotor stimulants

Antagonism of several characteristic effects of amphetamine and cocaine by the alpha adrenergic receptor antagonist prazosin is a most recent example of noradrenergic mechanisms in the actions of psychomotor stimulants (Tessel and Barrett 1986). We investigated whether or not prazosin may attenuate the disruptive effects of amphetamine on social and aggressive behavior in mice and squirrel monkeys (Miczek, unpublished observations). Pretreatment with prazosin (0.4 mg/kg) attenuated the disruption of attack... 

Both amphetamine and cocaine have also been reported to support intracranial self-administration in the mesolimbic/mesocortical dopaminergic system. Rats will self-administer cocaine into the medial prefrontal cortex (Goeders and Smith 1983). while amphetamine is self-administered into the orbitofrontal cortex of rhesus monkeys (Phillips and Rolls 1981) and the nucleus accumbens of rats (Hoebel et al. 1983 Monaco et al. 1981). These data indicate that the mesolimbic/mesocortical dopaminergic system is involved in the initiation of stimulant reinforcement processes, and this work suggests that the region of the nucleus accumbens, more specifically the mesolimbic dopamine system, may be an important substrate for reinforcing properties of several psychomotor stimulant drugs. 

This drug class includes cocaine and amphetamine derivatives 916 Transporters for dopamine (DAT), serotonin (SERT) and norepinephrine (NET) are the initial targets for psychomotor stimulants 916 Cocaine and amphetamines produce neuronal adaptations by repeatedly elevating monoamine levels 917... 

Cocaine, amphetamine, dextroamphetamine, methylphenidate, and pemoline are classified as psychomotor stimulants, producing an acute euphoria in control subjects, as well as a wide variety of responses in psychiatric patients. These stimulants are also effective in postponing the deterioration in psychomotor performance that often accompanies extreme fatigue, a property that may be useful in some carefully selected cases. 

Although there is no doubt that amphetamines or other psychomotor stimulants induce an initial euphoria, there is considerable doubt that they can serve as long-lasting antidepressants. Cocaine, for example, produces a euphoria almost immediately after i.v. injection and within a few minutes after intranasal administration, but the euphoria, as well as the tachycardia, decrease at a slightly faster rate than the level of plasma cocaine. A second dose given 1 hour later fails to produce a similar level of euphoria or tachycardia, suggesting a rapid tachyphylaxis. 

The psychomotor stimulants, cocaine and D-amphetamine, are considered together because they share a similar psychopharmacological profile.19 20 Low to moderate doses of both drugs given acutely to nontolerant, nonanxious subjects produce increases in positive mood (euphoria), energy, and alertness. Experienced cocaine users were unable to distinguish between intravenous (IV) cocaine and D-amphetamine,21 and cross-tolerance between cocaine and D-amphetamine with respect to their anorectic effect has been demonstrated.22 Additionally, the toxic psychosis observed after days or weeks of continued use of both psychostimulants is very similar. The fully developed toxic syndrome, characterized by vivid auditory and visual hallucinations, paranoid delusions, and... 

This effect is not surprising Amphetamines are potent psychomotor stimulants. Whether sniffed, swallowed, snorted, or injected, they induce feelings of power, strength, exhilaration, self-assertion, focus, and enhanced motivation. Amphetamine intake causes a release of the excitatory neurotransmitters dopamine and noradrenaline (norepinephrine) in the central nervous system (CNS). The release of dopamine typically induces a sense of aroused euphoria that may last several hours unlike cocaine, amphetamine is not readily broken down by the body. After taking amphetamines, feelings are intensified, the need to sleep or eat is diminished, and the user may feel as though he or she can take on the world. ... 

Cocaine is a powerful psychomotor stimulant, commonly used as a drug of abuse. Its actions are very like those of the amphetamines. It works by blocking reuptake of catecholamines within the central (and peripheral) nervous systems and is an Indirect sympathomimetic. 

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