雌激素对慢性脑缺血大鼠海马微血管构筑的影响

Effects of estrogen on dynamic changes of rat hippocampal microvascualr architecture during the chronic cerebral ischemia

目的：探讨雌激素对慢性脑缺血大鼠海马微血管构筑的影响.方法：采用永久性结扎去势大鼠双侧颈总动脉的方法建立慢性脑缺血模型,项背部皮下注射雌激素.单宁酸-氯化铁媒染法观察大鼠海马微血管构筑的动态变化,采用MiVnt图像分析系统对大鼠海马水平部的微血管密度（MVD）和微血管面积密度（MVA）进行定量分析.结果：模型组大鼠各时间点海马的MVA、MVD值均较正常对照组大鼠明显降低,且随着时间的延长,MVA、MVD值逐渐下降.雌激素治疗组大鼠各时间点海马的MVA、MVD值高于模型组同时间点,且随着用药时间的延长MVA、MVD逐渐上升.结论：雌激素可改善慢性脑缺血大鼠海马的微血管构筑,降低缺血、缺氧对于海马神经元的损伤.

Objective： To investigate the effects of estrogen on dynamic changes of rat hippocampal microvascualr architecture during chronic cerebral ischemia. Methods： The chronic cerebral ischemia rat model was established by permanently ligating the common carotid arteries on both sides of castrated rats, and the rat model was subcutaneously injected estrogen at nucha and back. TA-FE method was used to observe the dynamic changes of hippocampal microvascualr architecture; MiVnt image analytical system was used to quantitatively analyze the microvessel density （MVD） and micorvessel area density （MVA） of horizontal part of hippoeampus. Results： The MVD and MVA of hippocampus of model rats at each time point were obviously decreased compared with the normal control rats; and with time extension, the MVD and MVA were gradually decreasing. The MVD and MVA of hippocampus of rats in the estrogen group at each time point were obviously higher than those of model rats at the same time point; and with time extension, the MVD and MVA were gradually increasing. Conclusion： Estrogen can improve the microvascular architecture of hippocampus of chronic cerebral ischemia rats, degrade damages on hippocampus neurons induced by ischemia and hypoxia.