AUTORADIOGRAPHICAL STUDY OF TYPE-1 AND TYPE-2 OF BENZODIAZEPINE RECEPTORS IN RAT-BRAIN AFTER CHRONIC ETHANOL TREATMENT AND ITS WITHDRAWAL

The effect of chronic ethanol treatment, and its withdrawal on benzodi azepine binding sites in rat brain is described in this autoradiograph ical study using the benzodiazepine agonist [H-3]flunitrazepam. Severa l areas of the rat cerebral cortex, hippocampus, mesencephalon, cerebe llum and lateral geniculate nucleus were studied in animals, chronical ly treated with ethanol, and 24 or 48 hr after ethanol withdrawal. The [H-3]flunitrazepam binding and the relative percentages of binding to BZ1 and BZ2 sites, using zolpidem as a BZ1 site inhibitor, are descri bed. The cerebellum and red nucleus, which only express BZ1 binding si tes, appear to be areas significantly modified by ethanol and its with drawal. In no other structure did ethanol modify [H-3]flunitrazepam bi nding nor change the relative percentage of BZ1 and BZ2 sites.