Winnicka M M, Braszko J J, Wiśniewski K
Department of Pharmacology, Biatystok University Medical School, Poland.
Gen Pharmacol. 1998 May;30(5):801-5. doi: 10.1016/s0306-3623(97)00152-3.
We have previously shown that facilitatory effect of angiotensin II (AII) on the retrieval of memory is mediated by the dopaminergic system. In the present study, we searched for the influence of the 3-7 fragment of angiotensin II [AII(3-7)] on the retrieval processes in a passive avoidance situation after bilateral 6-OHDA lesions to the central amygdala (CA) and the CA4 field of the hippocampus (HI). AII(3-7) given 15 min before the retention testing, at the intracerebroventricular dose of 1 nmol, significantly prolonged avoidance latencies in sham-operated rats (i.e. improved retrieval of memory for the electric footshock experienced during the learning trial). Bilateral lesions to CA totally abolished, and to HI significantly diminished, this facilitatory effect. An increase of spontaneous locomotor activity in rats lesioned to CA and a decrease in rats lesioned to HI were unlikely to interfere with the cognitive effect of AII (3-7). These results suggest that the anatomical substrate of facilitating retrieval of information activity of AII(3-7) is closely related to the dopaminergic projection from the ventral tegmental area and substantia nigra to CA and HI.
我们之前已经表明，血管紧张素II（AII）对记忆提取的促进作用是由多巴胺能系统介导的。在本研究中，我们探究了血管紧张素II的3-7片段[AII(3-7)]对双侧6-羟基多巴胺损伤中央杏仁核（CA）和海马CA4区（HI）后被动回避情境中记忆提取过程的影响。在保留测试前15分钟，以1 nmol的脑室内剂量给予AII(3-7)，显著延长了假手术大鼠的回避潜伏期（即改善了对学习试验期间经历的电足电击的记忆提取）。双侧损毁CA完全消除了这种促进作用，而损毁HI则显著减弱了这种促进作用。CA损毁大鼠的自发运动活动增加以及HI损毁大鼠的自发运动活动减少不太可能干扰AII(3-7)的认知效应。这些结果表明，AII(3-7)促进信息提取活动的解剖学基础与从腹侧被盖区和黑质到CA和HI的多巴胺能投射密切相关。
