【摘要】 目的 观察促红细胞生成素（EPO）对窒息诱导新生大鼠脑损伤和CoCl₂诱导人脑胶质瘤细胞系U251缺氧的改善作用。方法 （1）7日龄SPF级新生Wistar大鼠随机分为对照组、窒息组、EPO组，每组22只。窒息组和EPO组新生大鼠采用常压窒息法构建脑损伤模型。EPO组脑损伤模型大鼠腹腔注射5 000 IU/（kg·d）的EPO，连续注射14 d；窒息组脑损伤模型大鼠注射等体积的生理盐水，连续注射14 d；对照组不注射生理盐水和EPO。每组取10只大鼠，采用Morris水迷宫实验观察各组新生大鼠空间记忆能力，包括逃避潜伏期、上台前游泳路程、90 s内穿越原平台次数、平台内运动距离、平台滞留时间、穿越有效区域次数、有效区域内运动距离和有效区域内滞留时间。采用旷场实验观察各组新生大鼠自主运动能力，包括运动总路程、中央区域路程和平均速度。每组取6只大鼠，连续干预第3天和第7天时断头处死，取大鼠大脑称重并计算脑组织含水量，采用速率法检测血清脑损伤标志物乳酸脱氢酶（LDH）。（2）人脑胶质瘤细胞系U251分为空白对照组、CoCl₂组、EPO组，CoCl₂组加入CoCl₂制备缺氧模型，EPO组加入CoCl₂和EPO，空白对照组加入等量培养液，继续培养24 h。采用CCK-8法测算各组细胞存活率，采用流式细胞术测算各组细胞凋亡率，采用比色法测算各组细胞上清液LDH。结果 （1）与对照组比较，窒息组新生大鼠的逃避潜伏期、上台前游泳路程、干预第3天和第7天脑组织含水量及血清LDH水平显著升高（P均<0.05）；与窒息组相比，EPO组新生大鼠的逃避潜伏期、上台前游泳路程、干预第3天和第7天脑组织含水量及血清LDH水平显著降低（P均<0.05）。与对照组比较，窒息组新生大鼠90 s内穿越原平台次数、平台内运动距离、平台滞留时间、穿越有效区域次数、有效区域内运动距离、有效区域内滞留时间、运动总路程、中央区域路程、平均速度均显著降低（P均<0.05）；与窒息组相比，EPO组新生大鼠90 s内穿越原平台次数、平台内运动距离、平台滞留时间、穿越有效区域次数、有效区域内运动距离、有效区域内滞留时间、运动总路程、中央区域路程、平均速度均显著升高（P均<0.05）。（2）EPO组细胞存活率高于CoCl₂组（P<0.05），细胞凋亡率、细胞上清液LDH水平均低于CoCl₂组（P均<0.05）。结论EPO能够改善窒息后脑损伤大鼠的空间记忆能力、自主运动能力和脑水肿程度，改善脑损伤。EPO能够升高CoCl₂诱导的缺氧U251细胞存活率，降低细胞凋亡率和细胞上清液LDH水平。更多还原

【Abstract】 Objective To observe the effects of erythropoietin（EPO） on asphyxia-induced brain injury in neonatal rats and hypoxia induced by CoCl₂ in human glioma cell line U251. Methods（1） 7-day-old SPF newborn Wistar rats were randomly divided into the control group, asphyxia group, and EPO group, with 22 rats in each group. Neonatal rats in the asphyxia group and EPO group were subjected to normal pressure asphyxia to establish brain injury models. Rats in the EPO group were injected intraperitoneally with 5 000 IU/（kg·d） EPO for 14 days, while rats in the asphyxia group were injected with the same volume of normal saline for 14 days. Rats in the control group were not injected with normal saline and EPO. Morris water maze test was used to observe the spatial memory ability of 10 rats in each group; it included escape latency, swimming distance before going on stage, the number of crossing the original platform in 90s, the movement distance in the platform, the residence time in the platform, the number of crossing the effective region, the movement distance in the effective region and the residence time in the effective region. The open field experiment was used to observe the autonomous movement ability of the newborn rats in each group, including the total distance, the distance in the central region and the average speed. Six rats in each group were decapitated and killed on the 3rd and 7th days after intervention. The rats’ brains were weighed and the water content of brain tissue was calculated. The lactate dehydrogenase（LDH） of brain injury markers in serum were detected by velocity method.（2） Human glioma cell line U251 was divided into the blank control group, CoCl₂ group and EPO group. Hypoxia models were made by adding CoCl₂ in the CoCl₂group and EPO in the EPO group, and the same amount of culture medium was added in blank control group for 24 h. Cell survival rate was measured by CCK-8, apoptosis rate was measured by flow cytometry, and LDH in supernatant was measured by colorimetric method. Results（1） Compared with the control group, the escape latency, the swimming distance before going on stage, the water content of brain on the 3rd and 7th days after intervention and the level of serum LDH in the asphyxia group significantly increased（all P<0. 05）. Compared with the asphyxia group, the water content of brain and the level of serum LDH in the asphyxia group significantly increased（all P<0. 05）, the escape latency, swimming distance before going on stage, brain water content and serum LDH level of neonatal rats in EPO group were significantly lower than those in the control group（all P<0. 05）. Compared with the control group, the number of traversing the original platform within 90 s, the distance of traversing the platform, the time of traversing the platform, the time of traversing the effective region, the distance of traversing the effective region, the time of staying in the effective region, the total distance of the movement, the distance of the central region and the average speed all decreased significantly in the asphyxia group（all P<0. 05）. Compared with the asphyxia group, the number of traversing the original platform within 90 s, the distance of traversing the platform, the time of traversing the platform, the time of traversing the effective region, the distance of traversing the effective region, the time of staying in the effective region, the total distance of the movement, the distance of the central region and the average speed all increased significantly in EPO group（all P<0. 05）.（2） The survival rate of cells in the EPO group was higher than that in the CoCl₂ group（P<0. 05）, but the apoptosis rate and LDH level in supernatant of cells were lower in the EPO group than in the CoCl₂ group（all P<0. 05）. Conclusions EPO could improve the spatial memory ability, spontaneous movement ability, and alleviate brain edema and brain injury in asphyxiated rats with brain injury. EPO could increase the survival rate of U251 cells induced by CoCl₂ and decrease the apoptosis rate and LDH level in the supernatant of U251 cells.更多还原