关键词: 七氟醚, 缺血再灌注, 神经保护, 星形胶质细胞, 动力学, 成神经细胞, 胶质瘢痕, 神经网络, 脑卒中, 吸入麻醉药

Abstract:

Astrocytes, the major component of blood-brain barriers, have presented paradoxical profiles after cerebral ischemia and reperfusion in vivo and in vitro. Our previous study showed that sevoflurane preconditioning improved the integrity of blood-brain barriers after ischemia and reperfusion injury in rats. This led us to investigate the effects of sevoflurane preconditioning on the astrocytic dynamics in ischemia and reperfusion rats, in order to explore astrocytic cell-based mechanisms of sevoflurane preconditioning. In the present study, 2,3,5-triphenyltetrazolium chloride staining and Garcia behavioral scores were utilized to evaluate cerebral infarction and neurological outcome from day 1 to day 3 after transient middle cerebral artery occlusion surgery. Using immunofluorescent staining, we found that sevoflurane preconditioning substantially promoted the astrocytic activation and migration from the penumbra to the infarct with microglial activation from day 3 after middle cerebral artery occlusion. The formation of astrocytic scaffolds facilitated neuroblasts migrating from the subventricular zone to the lesion sites on day 14 after injury. Neural networks increased in the infarct of sevoflurane preconditioned rats, consistent with decreased infarct volume and improved neurological scores after ischemia and reperfusion injury. These findings demonstrate that sevoflurane preconditioning confers neuroprotection, not only by accelerating astrocytic spatial and temporal dynamics, but also providing astrocytic scaffolds for neuroblasts migration to ischemic regions, which facilitates neural reconstruction after brain ischemia.

Key words: nerve regeneration, sevoflurane, ischemia and reperfusion, neuroprotection, astrocytes, dynamics, neuroblast, glial scar, neural network, stroke, inhalational anesthetics, neural regeneration