Chapter 12 - PHENCYCLIDINE RECEPTORS IN BRAIN: CURRENT METHODOLOGICAL ISSUES

Abstract

In 1979, two groups independently reported the detection of specific [ 3 H]phencyclidine ([ 3 H]PCP) binding sites in homogenates of rat brain. These sites appeared to constitute molecular targets for the actions of PCP and related drugs. Other groups have subsequently also reported such findings. This chapter focuses on the methodological aspects of the demonstration and characterization of these binding sites. Specific [ 3 H]PCP binding in brain tissue homogenates can be quickly and reliably assayed by rapid filtration. The findings, thus, obtained have been validated by additional techniques. These include centrifugation, slide-mounted brain slice, and autoradiographic binding methodologies. The results of properly conducted [ 3 H]PCP binding studies are highly reliable and consistent. [ 3 H]PCP binding displays the biochemical and anatomical characteristics required of a pharmacologically relevant synaptic recognition site initiating the unique psychotropic actions of PCP and related drugs. In combination with other techniques, the [ 3 H]PCP binding assay promises to permit elucidation of the functional roles of the PCP binding sites in relation to neuronal circuitry and perhaps to psychiatric disease.