EFFECT OF CHRONIC TREATMENT WITH ETHANOL AND WITHDRAWAL OF ETHANOL ON BINDING OF [H-3] SCH23390 TO D1 DOPAMINE-RECEPTOR IN RAT VISUAL-CORTEX AND HIPPOCAMPUS - AN AUTORADIOGRAPHIC STUDY

Male Wistar rats, treated with ethanol for 8 weeks and pair-control animals, were used to study the effects of chronic treatment with ethanol, and withdrawal of ethanol for 24 and 48 hr on [H-3]SCH23390 binding. The visual cortex (Laminae III-IV and Lamina VI), the superficial grey layer of the superior colliculus, and the molecular layer of the dentate gyrus of the hippocampus were the cerebral areas analysed. Non significant changes were observed in hippocampus and Laminae III-IV of the visual cortex after treatments with alcohol. More interesting results were obtained from Lamina VI, where the chronic treatment with ethanol did not modify the binding of [H-3]SCH23390, whereas the withdrawal of ethanol produced a statistically significant increase in binding values. In addition, superficial grey layer of the superior colliculus showed a significant increase in binding values between 48 hr withdrawal and ethanol treated groups. The results herein reported suggest that some structures involved in visual functions are related to responses of adaptation to ethanol.