目的:观察叔丁基对苯二酚对脑缺血再灌注后大鼠线粒体通路第2个天冬氨酸特异性半胱氨酸蛋白酶激活物（Smac）和凋亡抑制蛋白（XIAP）表达的影响。方法:2019年3-12月选取45只健康雄性SD大鼠，对大鼠进行随机编号并采用随机数表法分为假手术组、模型组与叔丁基对苯二酚组。通过结扎大鼠左颈动脉法建立脑缺血再灌注模型，并检测各组大鼠神经功能评分，剔除造模失败大鼠，每组各保留10只大鼠。分别于大鼠脑缺血再灌注后0.5 h、12 h对各组大鼠进行药物灌胃治疗，叔丁基对苯二酚组采用12.5 mg/kg叔丁基对苯二酚灌胃，假手术组与模型组采用等体积0.9%氯化钠注射液灌胃。再灌注24 h后，检测各组大鼠神经功能评分，之后处死大鼠，断头取脑。通过TUNEL法检测各组大鼠神经细胞凋亡情况；采用酶联免疫吸附法检测各组大鼠脑组织超氧化物歧化酶（SOD）、丙二醛（MDA）、肿瘤坏死因子α（TNF-α）、白细胞介素1β（IL-1β）表达水平；通过免疫组化法与蛋白质印迹法（Western blot）分别检测大鼠XIAP、Smac阳性细胞计数与蛋白表达水平。结果:叔丁基对苯二酚组大鼠神经功能评分为（1.36±0.49）分，明显低于模型组的（3.73±0.97）分（n t=6.896，n P<0.001），缺血侧皮质区仍可见大量神经细胞凋亡，但数量少于模型组。模型组大鼠脑组织SOD水平明显低于假手术组，MDA、TNF-α、IL-1β水平明显高于假手术组［SOD：（51.94±3.46）U/mg<（70.68±2.67）U/mg，n t=13.560，n P（1.20±0.96）nmol/mg，n t=11.479，n P（40.53±4.35）pg/mg，n t=14.353，n P（17.22±2.31）pg/mg，n t=10.639，n P<0.001］。叔丁基对苯二酚组大鼠脑组织SOD水平相对模型组明显上调，MDA、TNF-α、IL-1β水平明显下降［SOD：（51.94±3.46）U/mg<（68.84±5.03）U/mg，n t=8.754，n P（2.46±0.48）nmol/mg，n t=11.153，n P（57.64±6.22）pg/mg，n t=8.617，n P（23.84±5.48）pg/mg，n t=6.346，n P（12.39±3.18），n t=5.992，n P（5.64±1.35），n t=18.759，n P（0.24±0.05），n t=9.721，n P（0.36±0.05），n t=11.200，n P（22.63±4.37），n t=6.543，n P<0.001；Smac：（31.74±4.26）<（47.58±6.94），n t=6.151，n P（0.53±0.08），n t=6.420，n P<0.001；Smac：（0.70±0.09）<（0.92±0.15），n t=3.977，n P<0.001］。n 结论:叔丁基对苯二酚能够有效减少脑缺血再灌注后神经细胞凋亡，降低脑组织氧化应激及炎性反应，其作用可能与调节XIAP、Smac信号通路有关。“,”Objective:To investigate the effects of tert-butyl hydroperoxide (TBH) on the expression of second mitochondria-derived activator of caspase (Smac) and X-linked inhibitor of apoptosis (XIAP) in mitochondrial pathway after cerebral ischemia/reperfusion injury in rats.Methods:From March to December in 2019, 45 healthy male Sprague-Dawley rats were randomly divided into sham-operation, model and TBH groups. Rat models of cerebral ischemia/reperfusion injury were established by ligation of the left carotid artery. Rat neurological function was evaluated to exclude the rats that failed in cerebral ischemia/reperfusion injury induction. Ten rats were left in each group. At 0.5 and 12 hours after cerebral ischemia/reperfusion injury, rats in the TBH group were treated by intragastric administration of 12.5 mg/kg TBH and those in the sham-operation and model groups were identically treated by intragastric administration of equal volume of 0.9% sodium chloride injection. After 24 hours of reperfusion, rat neurological function was assessed in each group. Then the rats were killed and the brains were harvested. Apoptosis of nerve cells was detected by terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) assay. The levels of superoxide dismutase (SOD), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in the brain tissue were detected by enzyme-linked immunosorbent assay. XIAP- and Smac-positive cell count and protein expression were determined by immunohistochemical staining and western blot assay, respectively.Results:Rat neurological function score in the TBH group was significantly lower than that in the model group [(1.36 ± 0.49) points n vs. (3.73 ± 0.97) points, n t = 6.896, n P < 0.001]. In the TBH group, a large number of apoptotic nerve cells were found in the ischemic cerebral cortex, but the number of apoptotic nerve cells in the TBH group was significantly smaller than that in the model group. In the model group, SOD level was significantly lower, MDA, TNF-α and IL-1β levels were significantly higher compared with the sham-operation group [SOD: (51.94 ± 3.46) U/mg n vs. (70.68 ± 2.67) U/mg, n t = 13.560, n P < 0.001; MDA: (5.69 ± 0.78) nmol/mg n vs. (1.20 ± 0.96) nmol/mg, n t = 11.479, n P < 0.001; TNF-α: (89.36 ± 9.84) pg/mg n vs. (40.53 ± 4.35) pg/mg, n t = 14.353, n P < 0.001; IL-1β: (41.35 ± 6.79) pg/mg n vs. (17.22 ± 2.31) pg/mg, n t = 10.639, n P < 0.001]. In the TBH group, SOD level was significantly higher, MDA, TNF-α and IL-1β levels were significantly lower compared with the model group [SOD: (51.94 ± 3.46) U/mg n vs. (68.84 ± 5.03) U/mg, n t = 8.754, n P < 0.001; MDA: (5.69 ± 0.78) nmol/mg n vs. (2.46 ± 0.48) nmol/mg, n t = 11.153, n P < 0.001; TNF-α: (89.36 ± 9.84) pg/mg n vs. (57.64 ± 6.22) pg/mg, n t = 8.617, n P < 0.001; IL-1β: (41.35 ± 6.79) pg/mg n vs. (23.84 ± 5.48) pg/mg, n t = 6.346, n P < 0.001]. XIAP- and Smac-positive cell count and protein expression in the model group were significantly greater than those in the sham-operation group [XIAP-positive cell count: (22.63 ± 4.37) n vs. (12.39 ± 3.18), n t = 5.992, n P < 0.001, Smac-positive cell count: (47.58 ± 6.94) n vs. (5.64 ± 1.35), n t = 18.759, n P < 0.001; XIAP protein expression: (0.53 ± 0.08) n vs. (0.24 ± 0.05), n t = 9.721, n P ( 0.36 ± 0.05), n t = 11.200, n P < 0.001 ]. In the TBH group, XIAP-positive cell count and XIAP protein expression were significantly higher and Smac-positive cell count and Smac protein expression were significantly lower compared with the model group [XIAP-positive cell count: (36.78 ± 5.26) n vs. (22.63 ± 4.37), n t = 6.543, n P < 0.001, Smac-positive cell count: (31.74 ± 4.26) n vs. (47.58 ± 6.94), n t = 6.151, n P < 0.001; XIAP protein expression: (0.79 ± 0.10) n vs. (0.53 ± 0.08), n t = 6.420, n P < 0.001, Smac protein expression: (0.70 ± 0.09) n vs. (0.92 ± 0.15), n t = 3.977, n P < 0.001].n Conclusion:TBH can effectively reduce neuronal apoptosis, oxidative stress and inflammatory reaction after cerebral ischemia/reperfusion injury, which may be related to the regulation of XIAP and Smac signaling pathways.