Behavior amphetamine

Repeated intermittent exposure to stimulants can produce sensitization, where subsequent drag exposures produce increased behavioral and neurochemical responses. The ability of the drag and ultimately of related stimuli to elicit behavior may be increased with repeated administration or intake of the drag. Dopaminergic sensitization within the amygdala has also been found after repeated exposure to amphetamine and this... 

The various stimulants have no obvious chemical relationships and do not share primary neurochemical effects, despite their similar behavioral effects. Cocaines chemical strucmre does not resemble that of caffeine, nicotine, or amphetamine. Cocaine binds to the dopamine reuptake transporter in the central nervous system, effectively inhibiting dopamine reuptake. It has similar effects on the transporters that mediate norepinephrine and serotonin reuptake. As discussed later in this chapter in the section on neurochemical actions mediating stimulant reward, dopamine is very important in the reward system of the brain the increase of dopamine associated with use of cocaine probably accounts for the high dependence potential of the drug. 

Stimulants induce both tolerance and sensitization to their behavioral effects. Tolerance develops to the anorectic and euphoric effects of stimulants (Schuster 1981) however, chronic intermittent use of low doses of stimulants delays the development of tolerance. With the doses commonly used in clinical practice, patients treated for narcolepsy or for depressive or apathetic states find that the stimulant properties usually persist without development of tolerance however, the persistence of antidepressant effects remains a matter of controversy. Sensitization has been linked to the development of amphetamine-induced psychosis (Yui et al. 1999). Sensitization to the induction of psychosis is suggested because psychosis is induced by progressively lower doses and shorter periods of consumption of amphetamine following repeated use over time (Sato 1986). Sensitization for amphetamine-induced psychosis may persist despite long periods of abstinence. 

The development of effective pharmacotherapy has lagged behind progress in understanding the reward mechanisms and chronic impairments underlying stimulant abuse. Pharmacological and behavioral treatment approaches that have been used for cocaine abuse have not been as widely tested for the treatment of amphetamine abuse, limiting what can be offered for treatment of this disorder. No treatment agents are approved by the FDA for treatment of cocaine or amphetamine dependence. 

Ellinwood EH Jr, Sudilovsky A, Nelson LM Evolving behavior in the clinical and experimental amphetamine (model) psychosis. Am J Psychiatry 130 1088—1093, 1973... 

Martin WR, Sloan JW, Sapira JD, et al Physiologic, subjective, and behavioral effects of amphetamine, methamphetamine, ephedrine, phenmetrazine, and methylphenidate in man. Clin Pharmacol Ther 12 245-258, 1971 McCormick TC Jr, McNeil TW Acute psychosis and Ritalin abuse. Tex State J Med... 

Harris, R.A. Snell, D. and Lol, H.H. Effects of 7-amphetamine, monomethoxyamphetamines and hallucinogens on schedule controlled behavior. J Pharmacol Exp Ther 204 103-117, 1978,... 

Case reports and survey data provide a complex account of the link between amphetamines and aggressive behavior, leading to sharply differing... 

Reductions in aggressive behavior after treatment with amphetamine and other psyehomotor stimulants are seen in children and adolescents who have been diagnosed with hyperkinesis or attention deficit disorder. There is considerable disagreement about these diagnostic categories and about whether the violent outbursts and uncontrolled episodes of aggressive behavior are limited to the early developmental period or continue into adulthood (Mendelson et al. 1971 Minde et al. 1972). 

The early report by Bradley (1937) on beneficial treatment effects with amphetamine in aggressive, destructive, irritable, and hyperactive boys was repeatedly eonfirmed by double-blind, placebo-controlled studies. Significant reductions in aggressive behavior and improvements in social interactions were found after treatment with 10 to 40 mg/day of d- or /-amphetamine for boys and girls, 5 to 14 years of age, who had been diagnosed as... 

In situations of social conflict, amphetamine increases the frequeney of escape and defensive responses to threats and attacks by a stimulus animal in mice, rats, cats, rhesus monkeys, and squirrel monkeys in a dose-dependent manner (Hoffmeister and Wuttke 1969 Crowley et al. 1974 Miczek and O Donnell 1978 Miczek 1979 Schlemmer and Davis 1981 Haber et al. 1981). Even in the absence of a distinctive behavioral stimulus from an opponent, amphetamine induces escape and defensive responses in mice. Krsiak considered these unprovoked defensive and escape responses as signs of timidity (Krsiak 1975 Krsiak 1979 Poschlova et al. 1977). 

Sequences of aggressive behavior that are composed of characteristic acts and postures following each other rapidly are disrupted. These disorganizing effects parallel the analysis of amphetamine effects on other intricately patterned behaviors such as feeding, maternal care, play behavior, or reproductive interactions. For example, amphetamine suppresses play... 

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