ETHANOL AND DIAZEPAM INHIBITION OF HIPPOCAMPAL LTP IS MEDIATED BY ANGIOTENSIN-II AND AT(1) RECEPTORS

Angiotensin II (AII) inhibits the induction of hippocampal long-term p otentiation (LTP), a frequency-dependent model of learning and memory. These results demonstrate that the dose-dependent inhibition of LTP d ue to ethanol (EtOH) and diazepam (DZ) involves AII. Inhibition of LTP induction by All, EtOH, and DZ can be blocked by All receptor antagon ists saralasin and lorsartan (DuP 753). Lorsartan is a competitive ant agonist of the AT1 subtype All receptor. Therefore, the EtOH and DZ in hibition of LTP induction is mediated by AT1 receptors. These results indicate a new role for AII in the brain in the possible mediation of memory deficits associated with alcohol and the benzodiazepines.