Behavioral and Biochemical Analysis of the Dependence Properties of Nicotine

Our recent studies on the reinforcing properties and psychotoxicity of nicotine in rats and rhesus monkeys are introduced. In drug discrimination experiments in rats, the discriminative effects of subcutaneous nicotine were generalized by the nicotine injected into nucleus accumbens or medical prefrontal cortex. In microdialysis in rats, nicotine increased dopamine (DA) and DOPAC at nucleus accumbens and striatum. In self-administration experiments in monkeys, faster infusion speeds resulted in higher intake rates of nicotine and possible development of physical dependence attenuated monkey’s nicotine-seeking behavior. The threshold dose for reinforcing effect of nicotine was found to be 2.5-10 µg/kg.