Computer-assisted autoradiographic localization of subtypes of serotonin1 receptors in rat brain.

In vitro light microscopic receptor autoradiography was carried out to localize two subtypes of 5-HT1 receptors in certain regions of the rat central nervous system (CNS). The data were analyzed by computerized digital image processing to reveal subfields of high receptor densities within the septal area, the prefrontal and frontal cortex, and the hippocampus. The septum and hippocampus showed interesting localization of serotonin binding which can be subtyped into 5-HT1-A and 5-HT1-B sites. The differential localization of these sites may be helpful in shedding some light as to the functional significance of multiple serotonin receptors.