Baclofen and AII 3-7 on learning and memory processes in rats chronically treated with ethanol

The aim of this study was to determine the possible influence of baclofen, an agonist of the GABA(B) receptor on behavioral activity (recall, acquisition of conditioned reflexes) of angiotensin II fragment 3-7 (AII 3-7) in rats chronically treated with ethanol. Long-term (9 weeks) ethanol intoxication profoundly impaired learning and memory processes in all tests used. The GABA(B) receptor agonist baclofen (0.75 mg/kg i.p.) did not influence exploratory and motor activity in the control rats, but we observed a tendency (without significance) to decrease the psychomotor activity in the alcohol-intoxicated groups of animals, when it was injected together with AII 3-7 (2 microg i.c.v.). Baclofen did not influence the retrieval process in the passive avoidance recall, and when it was given together with AII 3-7 did not change the positive action of this fragment in control groups, but significantly enhanced its action in the animals chronically treated with ethanol. Baclofen showed significant improvement of acquisition in the active avoidance test only in the alcohol-intoxicated groups. Baclofen, injected together with AII 3-7, yielded important attenuation action of AII 3-7 in the control groups in the first 3 days of test, but did not produce any changes during the fourth and fifth day of the experiment. Baclofen did not provoke any changes in activity of AII 3-7 (when it was injected together) in the acquisition of the active avoidance test in the alcohol-intoxicated groups of animals.