[Cannabinoid dependence in animal models]

A large number of psychoactive derivatives have been identified in Cannabis sativa preparations,but their potential ability to produce dependence in humans is still a controversial issue. Cannabinoids were considered different from other addictive drugs in terms of addictive potential and neurobiological targets of action. Experimental evidence indicates that the mesolimbic dopaminergic system is the common neuronal substrate for the motivational and rewarding properties of different drugs of abuse. Many studies have indeed revealed that an increase in extracellular dopamine concentration in the nucleus accumbens was observed after acute and chronic administration of cannabinoid receptor agonists. Many behavioral studies have used different animal models to clarify the consequences of chronic exposure to cannabinoid receptor agonists and the abuse liability of these compounds. This paper reviews research from animal models of cannabinoid addiction in which both motivational and physical aspects of dependence can be measured in order to clarify still unresolved issues of cannabinoid addiction.