七氟醚对大鼠海马脑片缺血损伤的保护作用

目的:探讨七氟醚对脑缺血损伤的保护作用及其机制。方法:用电生理细胞外记录的方法和组织学检查的技术,观察对照组、2%七氟醚组和4%七氟醚组对缺氧无糖(OGD)及谷氨酸(Glu)损伤所致的大鼠海马脑片CA1区顺向群峰电位(OPS)的影响及各组脑片超微结构的变化。结果:对照组和2%七氟醚组在OGD和Glu损伤后海马脑片OPS很难恢复;4%七氟醚组明显改善OPS的恢复程度和恢复率,减轻海马CA1区神经元细胞损伤。电镜观察可见,对照组OGD和Glu损伤后海马CA1区锥体细胞明显水肿,核膜不完整,核染色加深,核内染色质凝聚成块,胞浆中内质网高度扩张,线粒体水肿;2%七氟醚组与对照组相似;4%七氟醚组细胞水肿不显,核膜完整,核内染色质轻度凝聚,内质网轻度扩张,线粒体无明显水肿。结论:4%七氟醚对大鼠海马脑片OGD损伤有保护作用,可能与减轻兴奋性Glu毒性有关。

Neuroprotection of sevoflurane against the ischemia injury in hippocampal slices of rat

Aim:To study the protective effects and the mechanisms of sevoflurane on ischemic cerebral neurons.Methods:With electrophysiological microelectrode recoding technique,the OPS of hippocampal slices deprived with oxygen and glucose(OGD)and injured from toxicity of glutamate(Glu)in the control group,2% sevoflurane group and 4% sevoflurane group were observed.The changes of ultrastructure in the three groups were also observed respectively.Results:In the control group and 2% sevoflurane group it didn't show the improvement of recovery in OPS of hippocampal slices injured from OGD and Glu.In 4% sevoflurane group the recovery degree and the recovery rate of OPS were obversely.With electricmicroscope,it was founded that in the control group and 2% sevoflurane group,the pyramidal neurons in CA1 regions deprived with glucose and oxygen and exposured by Glu were damaged.Intercellular edema were severe,the nucleus membranes were not complete,the chromatin formed mass,the endoplasmic reticulum in the cytoplasm were degenerate,mitochondrion swelled.In 4% sevoflurane group,the pyramidal neurons in CA1 regions did not swell obviously,the nucleus was clear,the nucleus membranes were complete and the mitochondria swelled lightly.Conclusion:4% sevoflurane could ptotect hippocampal neurons deprived with glucose and oxygen from the damage.The probable mechanism is 4% sevoflurane reduced the excitatory of Glu.