Benzodiazepine receptors resolved.

To date, attempts to map the distribution and density of benzodiazepine receptors in the CNS have been dominated by radiohistochemical techniques with conventional receptor binding. Their limited resolution, however, prompted us to try an immunohistochemical approach. Purified GABA/benzodiazepine receptors, prepared from bovine cerebral cortex, have been used to raise monoclonal antibodies for this purpose. Immunoreactive sites in rat brain, spinal cord and retina as well as in bovine and post-mortem human brain were found to be concentrated on neuronal cell bodies and processes in those regions known to be innervated by GABAergic neurons. Electron microscopic analysis revealed a selective staining of axosomatic and axodendritic pre- and postsynaptic contacts.