Reinforcement methamphetamine

In humans, a comparative examination of the positive reinforcing effects of solvents showed that among inhalant-dependent subjects, solvents induced a more intense sensation of pleasant feelings than that induced by alcohol and nicotine in subjects addicted to these substances (Kono et al. 2001). Solvent-dependent subjects reported pleasant feelings comparable to those reported by stimulant-dependent subjects after use of methamphetamine. However,... 

Tolerance is characterized by reduced responsiveness to the initial effects of a drug after repeated exposure or reduced responsiveness to a related compound (i.e., cross-tolerance). Animal studies have not provided conclusive evidence of tolerance to the effects of the centrally active compounds in toluene or trichloroethane (Moser and Balster 1981 Moser et al. 1985). Observations in humans, on the other hand, have documented pronounced tolerance among subjects who chronically inhale substances with high concentrations of toluene (Glaser and Massengale 1962 Press and Done 1967) and butane (Evans and Raistrick 1987). Kono et al. (2001) showed that tolerance to the reinforcing effects of solvents is comparable to that conditioned by nicotine but less intense than that reported with alcohol or methamphetamine use. 

Ranaldi, R., Wise, R.A. Intravenous self-administration of methamphetamine-heroin (speedball) combinations under a progressive-ratio schedule of reinforcement in rats. Neuroreport. 11 2621, 2000. 

Ranaldi, R., Anderson, K.G., Carroll, F.I., Woolverton, W.L. Reinforcing and discriminative stimulus effects of RTI 111, a 3-phenyltropane analog, in rhesus monkeys interaction with methamphetamine. 

That impression gets of a lot of routine reinforcement from news sources. Chemistry is associated with pollution of the atmosphere by ozone and the noxious oxides of nitrogen and sulfur, oil spills, toxic pesticides and herbicides, smelly oil refineries, undesired food additives, chemical accidents, substances of abuse such as heroin, cocaine, and methamphetamine, and chemical weapons. Chemistry gets a lot of bad ink. 

Methamphetamine, known on the illicit market as speed, ice, or crystal, is a white crystalline powder, with a bitter taste and odor that dissolves easily in water or alcohol. Similarly to cocaine, it exerts a potent positive reinforcement and it is believed that the dextrorotatory form is responsible for the dopaminergic psychostimulant effect [15]. 

The most promising compound, UKCP-110, was evaluated for its ability to decrease methamphetamine self-administration and methamphetamine discriminative stimulus cues and for its effect on food-maintained operant responding. It is noteworthy that UKCP-110 decreased the number of methamphetamine self-infusions, while having no effect on food-reinforced behavior or the methamphetamine stimulus cue. Thus, UKCP-110 represents a new lead in the development of novel pharmacotherapies for the treatment of methamphetamine abuse. 

N ewman JL, Carroll ME (2006) Reinforcing effects of smoked methamphetamine in rhesus monkeys. Psychopharmacology 188 193-200... 

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