Kułakowska A, Karwowska W, Wiśniewski K, Braszko J J
Department of Pharmacology, Medical Academy of Białystok, Poland.
Pharmacol Res. 1996 Sep-Oct;34(3-4):109-15. doi: 10.1006/phrs.1996.0073.
The role of the angiotensin AT1 receptors in certain behavioural effects of angiotensin II (Ang II), using their selective antagonist losartan (DuP 753), was assessed. Ang II, given intracerebroventricularly (ICV) at the dose of 1 nmole, significantly improved object recognition, learning of conditioned avoidance responses (CARs), and recall of a passive avoidance behaviour. Losartan alone (1 microgram) was ineffective in any test except for the elevated 'plus' maze measuring anxiety which was diminished by the drug, both in peptide treated and in control rats. Losartan, given 5 min before Ang II, abolished improved after the peptide recall of the passive avoidance and object recognition. Losartan did not influence increased after Ang II rate of CARs acquisition. None of the treatments significantly changed behaviour of rats in the open field. The results point to the considerable involvement of the AT1 angiotensin receptors in the cognition improving effects of Ang II. However, unspecific psychoactivity of losartan should also be taken into account.
利用血管紧张素AT1受体的选择性拮抗剂氯沙坦（DuP 753），评估了血管紧张素AT1受体在血管紧张素II（Ang II）某些行为效应中的作用。以1纳摩尔的剂量脑室内注射（ICV）Ang II，可显著改善物体识别、条件性回避反应（CARs）的学习以及被动回避行为的记忆。单独使用氯沙坦（1微克）在任何测试中均无效，但在测量焦虑的高架“十”字迷宫中，该药物可减轻肽处理组和对照组大鼠的焦虑。在注射Ang II前5分钟给予氯沙坦，可消除肽给药后被动回避和物体识别记忆的改善。氯沙坦不影响Ang II给药后CARs习得率的增加。所有处理均未显著改变大鼠在旷场中的行为。结果表明，AT1血管紧张素受体在很大程度上参与了Ang II的认知改善作用。然而，也应考虑氯沙坦的非特异性心理活性。
