The role of androgen on brain protection by inhalation anestheticsduring cerebral reperfusion

围手术期脑缺血的诊断很困难，但脑梗塞的发作是致命的。因此，预防此类事件的发生对麻醉管理非常重要。脑梗塞发病率存在性别差异，总体上女性脑梗塞发病率低于男性。提示雌激素在这一机制中起重要作用。另一方面，关于雄激素在缺血事件中的作用的信息很少。有报道称，吸入麻醉剂诱导的预适应的神经保护作用仅见于男性，在女性中未见。这种性别差异可能与吸入麻醉剂对脑缺血的保护作用有关。然后，我们打算研究雄激素和七氟醚之间的相互作用对脑保护作用的影响。首先，为了评价I-…后脑内皮细胞的功能更多的缺血/再灌注，我们使用闭合颅窗准备结合大脑中动脉闭塞模型在SpragueDawley大鼠。为评价脑缺血再灌流前后的脑血管内皮功能，可局部应用乙酰胆碱。遗憾的是，吸入七氟烷对缺血/再灌流所致的血管内皮功能障碍无缓解作用。此外，我们还观察了主动脉阻断和开放后脊髓组织氧分压(PsptO2)的变化。在麻醉兔中，我们准备使用组织PO2监测来测量主动脉阻断后的PsptO2。在实验中，我们将18只动物分为3组，(D)对照组，(E)雌激素组(17β雌二醇：20μg)，n=6，(F)福维斯特(1 mg/kg)组，n=6。给予17β雌二醇可改善主动脉阻断后20min和开放后0、2、5min的PsptO2。用氟维司他处理后，这种改善作用减弱。较少

The diagnosis of perioperative cerebral ischemia is difficult, but the onset of cerebral infarction is fatal. Thus, the prevention of such event is very important for anestheticmanagement. Gender differences are observed in the incidence of cerebral infarction, and generally the incidence of cerebral infarction is less in females than males. It is suggested that the estrogen is strongly involved in this mechanism. On the other hand, there is little information about the role of androgen regarding ischemic events. It hasbeen reported that neuroprotective effect through preconditioning induced by inhalation anesthetic was found only in males, and not seen in females. There is a possibility that the gender difference is involved in the protective effect of inhaled anesthetic for the brain ischemia. Then we intended to investigate the interaction between androgen and sevoflurane regarding cerebral protective effect. Firstly, in order to evaluate thecerebral endothelial function following i … More schemia/reperfusion, we used the closed cranial window preparation associated with the middle cerebral artery occlusion model in the Sprague-Dawley rat. To evaluate the cerebrovascular endothelial function before and after cerebral ischemia/reperfusion, topical administration of acetylcholine could be applied.Unfortunately, by the inhalation of sevoflurane, the attenuation effect of vascular endothelial dysfunction caused by ischemia/reperfusion was not observed.Additionally, we evaluated the tissue oxygen partial pressure of spinal cord (PsptO2) following aortic cross-clamping and -unclamping. In anesthetized rabbits, we prepared for measurement of PsptO2 following aortic cross-clamping using tissue PO2 monitoring. In the experiment, we allocated 18 animals into 3 groups,(d) control group; n=6,(e) estrogen (17β estradiol: 20μg) group; n=6,(f) fulvestrant pretreatment (1mg/kg) groupn=6. Administration of 17β estradiol improved deterioration of the values in PsptO2 at 20 min after aortic cross-clamping and 0, 2, 5 min after aortic unclamp. The improvement was diminished by pretreatment of fulvestrant. Less