老龄大鼠慢性脑灌注不足与认知功能障碍的研究

目的　探讨老龄大鼠慢性脑灌注脑损害和认知功能障碍及其机制。方法　 5 0只老龄大鼠用于实验 ,其中 2 0只接受环孢菌素A(CsA)胃灌治疗。用光镜和电镜观察组织学改变 ,免疫组织化学法检测免疫细胞的活动 ,采用微机控制穿梭箱双向主动回避反应实验系统检测大鼠认知功能。结果　大鼠持久性双侧颈总动脉结扎 (2VO)诱导的慢性脑灌注不足造成了脑组织广泛免疫细胞活动和进行性脑损害 ,导致了大鼠进行性学习和记忆能力下降。CsA治疗组大鼠脑内免疫细胞的活动明显减少 ,脑损害明显减轻 ,学习和记忆能力显著提高。结论　脑组织免疫细胞的活动贯穿于大鼠慢性脑灌注不足脑损害的病理过程 ,在脑损害和认知功能障碍的发生和发展中起重要作用 ;CsA可明显减轻脑内免疫细胞的活动 ,防治了大鼠的脑损害和认知功能障碍。

Study on cognitive impairment after chronic cerebral hypoperfusion in aged rats

Objective To explore brain damages and cognitive impairment and their mechanism after chronic cerebral hypoperfusion(CCH)in aged rats.Methods Bilateral common carotid arteries were permanently double ligated in 50 Wistar rats.Twenty of them were administered cyclosporin A.Activation of immunocytes were observed with immunohistochemistry.Pathological changes of brain was observed with optical and electron microscopes.Cognitive function of rats was measured in a computer controlled two way active avoidance shuttle box.Results There were extensive activation of immunocytes in brain,progressive brain damages and obvious cognitive impairment in rats after CCH.In cyclosporin A treated rats,activation of immunocytes in brain was obviously reduced,brain damages was much less servere and cognitive function of rats was also improved.Conclusions There are progressive brain damages and cognitive impairment of rats which may result from activation of immunocytes in brain after CCH.Immunosuppressant cyclosporin A can suppress activation of immunocytes in brain and cure brain damages and cognitive impairment of rats after CCH.