颅脑手术中机械性脑血管痉挛后大脑中动脉内皮细胞的凋亡

目的 观察猫大脑中动脉（MCA）受机械性刺激痉挛后早期（2h内），血管壁和内皮细胞超微结构的变化。方法 6只猫，眶后入路，暴露右侧MCA，机械刺激MCA30rain，应用显微目镜的显微尺测量MCA直径的改变。激光多普勒仪纪录皮层脑血流灌流指数。电子显微镜观察刺激后2hMCA血管壁和内皮细胞超微结构的变化。结果 机械性刺激MCA后，MCA直径缩小，为刺激前的68．77％。脑组织灌流指数下降到刺激前的42．59％。刺激结束后2h，MCA直径恢复正常。脑组织灌流量恢复到刺激前的61．87％。电镜结果发现，MCA经急性机械性刺激后早期（2h）内皮细胞染色质边集，凝聚成新月形小体。线粒体嵴模糊不清。结论 机械性刺激猫脑MCA可致血管壁痉挛。刺激后早期（2h）即出现内皮细胞超微结构的变化，显示内皮细胞的凋亡现象。提示颅脑手术或动物实验中对脑血管的机械性刺激应尽可能的轻微，尽量减少对脑血管的机械性刺激，避免急性脑血管痉挛的发生，以减少副反应或假阳性实验反应.

Observation in Apotosis Structures of Middle Cerebral Artery Endotheliocyte at the Early Stage after Acute Mechanical Cerebral Vasospasm during the Craniocerebral Operation

ObjectiveTo observe the ultrastructures of vessel and endotheliocyte in the early stage(2 h after stimulation finished) after acute mechanical middle cerebral artery(MCA) vasospasm in cats.MethodsThe right MCA of 6 cats were mechanically stimulated using a small smooth stainless steel nail in the field acrossing the olfactory tract for 30 min.The diameter of MCA was recorded by metrical ocular of microscope.The changes of the perfusion index of brain tissue were observed through the Laser Doppler flowmetry monitor fixed on the skull.The ultrastructure of vessel and endotheliocyte were investigated through the electron microscope.ResultsThe diameter of MCA decreased to 68.78% of normal.2 h later,the diameter of MCA recovered.The perfusion index of the cortex surface decreased to 42.59% of normal and up to 61.87% 2 h later.The chromatin of endotheliocyte congregated to the side and formed the lunular body.The heaves of mitochondria(MIT) are blurry 2 hours after the mechanical stimulation.ConclusionThe persistent mechanical stimulation can cause acute cerebral vasospasm,which may involve the apoptosis of endotheliocyte of MCA.It is important to reduce the mechanical stimulus to the cerebral vessel in order to avoid acute cerebral vasospasm during clinical and basic craniotomy.