PARTICIPATION OF ANGIOTENSIN-II IN LEARNING AND MEMORY .2. INTERACTIONS OF ANGIOTENSIN-II WITH DOPAMINERGIC DRUGS

  • 1 April 1986
    • journal article
    • research article
    • Vol. 8  (4) , 203-206
Abstract
The effect of angiotensin II (ATII) and of its interactions with dopaminergic drugs injected post-trial on retention in active avoidance tasks in shuttle-box-trained rats were studied. ATII at doses of 0.10 and 0.50 .mu.g administered intracerebroventricularly (i.c.v.) immediately after training improved retention. The dopaminergic receptor agonist apomorphine at a dose of 0.10 mk/kg injected intraperitoneally (i.p.) facilitated retention whereas elymoclavine (a dopaminergic agonist) at a dose of 2.5 mg/kg i.p. had no effect. ATII at a dose of 0.10 .mu.g i.c.v. administered after apomorphine 0.10 mg/kg or elymoclavine 2.5 mg/kg exerted a stronger retention-facilitating effect. The dopaminergic receptor antagonists haloperidol at a dose of 1 mg/kg i.p. markedly impaired retention. ATII at a dose of 0.50 .mu.g administered after haloperidol (1 mg/kg) did not exercise its retention-facilitating effects. It is concluded that the retention facilitating effects of ATII are realized through interactions with brain dopaminergic transmission.