反复性脑缺血丘脑钙积聚与神经元损害

Calcium Accumulation and Neuronal Damage in the Rat Thaltamus Following Repeated Cerebral Ischemia

目的研究反复性脑缺血丘脑神经元的病理损害及其机制。方法 应用45Ca放射自显影及光镜对比研究大鼠单次性和反复性脑缺血及NMDA受体拮抗剂MK-801治疗后丘脑钙积聚和神经元损害的病理改变。结果 反复缺血组丘脑异常钙积聚与神经元损害明显重于单次缺血组;MK-801能显著减轻和改善丘脑钙积聚与组织病理损害。结论 反复非致死性短暂脑缺血导致丘脑腹侧神经元显著累积性损害,兴奋性氨基酸和Ca2+可能起着重要作用。

Objective To study the neuronal pathological damage and its mechanism of thalamus following repeated cerebral ischemia. Methods 45Ca autoradiography and light microscopy were used to determine the calcium accumulation and neuronal pathological changes of thalamus following repeated cerebral ischemia in the rats in comparison with the damage following single cerebral ischemia.The effect of MK-801,a NMDA receptor antagonist, was also examined.Results The abnormal calcium accumulation and neuronal injuries were found to be more severe in the thalamus in the group of repeated cerebral ischemia than those in the single ischemic insult group. MK-801 is effective in reducing or ameliorating the calcium accumulation and histopathological damage in the thalamus. Conclusion The present results suggested that the repeated nonlethal cerebral ischemia resulted in an intense cumulative damage in the ventral thalamus and the excitatory amino acid and Ca 2+ may play a major role in it.