ABSTRACT
Cocaine is a powerfully reinforcing drug exhibiting a complex set of pharmacological actions. Cocaine is known to inhibit synaptosomal uptake of dopamine, norepinephrine, and serotonin in vitro and has well-documented local anesthetic properties. The multiplicity of binding sites also requires an examination of the distribution of cocaine binding at concentrations which are relevant to those found in drug abusers, if one desires to correlate pharmacological and toxic effects of the drug with binding to particular brain regions. Although not tested directly in the human brain, it is reasonable to assume that cocaine binding to regions highly enriched in serotonin neurons and terminals, such as the raphe, hypothalmus, and substantia nigra, is also serotonergic rather than dopaminergic in nature. Cocaine analogues appear to bind to different subsets of cocaine binding sites depending on their structure. The action of cocaine on the serotonergic system may contribute to the reduction in sleep and the increased aggressive behavior seen during cocaine intoxication.
