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目的:观察白藜芦醇是否能改善脓毒症脑病（SAE）大鼠的认知功能障碍，并探讨其作用机制。方法:选择清洁级12周龄雄性SD大鼠，按随机数字表法分为假手术组、脓毒症模型组、白藜芦醇组，每组30只。采用尾静脉注射脂多糖（LPS）10 mg/kg复制脓毒症大鼠模型；假手术组以相同途径给予等量生理盐水。白藜芦醇组制模后腹腔注射白藜芦醇注射液8 mg·kgn -1·dn -1，每日1次，连用2 d；脓毒症模型组和假手术组以相同途径给予等量生理盐水。制模后24 h用水迷宫实验评估各组大鼠认知功能；同时测定脑组织含水量（BWC）、伊文思蓝（EB）渗漏量以评估血脑屏障（BBB）通透性；采用蛋白质免疫印迹试验（Western Blot）检测脑皮质组织基质金属蛋白酶9（MMP-9）、闭合蛋白（Occludin）和封闭蛋白5（Claudin-5）的蛋白表达；采用免疫荧光双标法测定MMP-9蛋白和星形胶质细胞标志蛋白（GFAP）在脑皮质组织的共定位情况。n 结果:与假手术组相比，脓毒症模型组制模后48 h、72 h大鼠逃逸潜伏期显著延长〔48 h逃逸潜伏期（s）：56.56±6.43比36.62±3.32，72 h逃逸潜伏期（s）：57.72±7.23比26.46±4.24，均n P<0.01〕，BWC、EB渗漏量显著增加〔BWC：（84.56±2.03）%比（76.82±2.22）%，EB渗漏量（μg/g）：17.56±2.28比6.25±1.36，均n P<0.01〕，大脑皮质组织MMP-9蛋白表达水平明显升高（MMP-9/β-actin：0.73±0.01比0.24±0.01，n P<0.01），Occludin和Claudin-5的蛋白表达水平明显降低（Occludin/β-actin：0.45±0.02比0.86±0.04，Claudin-5/β-actin：0.62±0.03比0.96±0.05，均n P<0.01）；同时伴随着MMP-9蛋白和脑皮质组织星形胶质细胞共定位表达增加〔MMP-9荧光强度（AU）：38.66±4.26比17.23±3.04，MMP-9阳性细胞百分比：（26.92±1.77）%比（12.82±1.46）%，均n P<0.01〕。与脓毒症模型组相比，白藜芦醇组大鼠逃逸潜伏期显著缩短〔48 h逃逸潜伏期（s）：41.42±6.27比56.56±6.43，72 h逃逸潜伏期（s）：33.46±7.17比57.72±7.23，均n P<0.01〕，BWC、EB渗漏量显著减少〔BWC：（77.15±2.27）%比（84.56±2.03）%，EB渗漏量（μg/g）：7.74±1.88比17.56±2.28，均n P<0.01〕，而大脑皮质组织MMP-9蛋白表达明显降低（MMP-9/β-actin：0.25±0.01比0.73±0.01，n P<0.01），Occludin和Claudin-5的蛋白表达均明显升高（Occludin/β-actin：0.82±0.03比0.45±0.02，Claudin-5/β-actin：0.92±0.04比0.62±0.03，均n P<0.01），同时伴随着MMP-9蛋白和脑皮质组织星形胶质细胞共定位表达减少〔MMP-9荧光强度（AU）：19.44±4.37比38.66±4.26，MMP-9阳性细胞百分比：（13.11±1.29）%比（26.92±1.77）%，均n P<0.01〕。n 结论:白藜芦醇通过抑制脓毒症大鼠大脑皮质组织星形胶质细胞MMP-9的表达，减少紧密连接蛋白Occludin、Claudin-5的降解，从而降低BBB通透性，最终改善SAE的认知功能障碍。“,”Objective:To explore the mechanism of resveratrol on ameliorating the cognitive dysfunction induced by sepsis associated encephalopathy (SAE) in rats.Methods:The 12 weeks old male Sprague-dawley (SD) male rats were randomly divided into sham group, sepsis group and resveratrol group, with 30 rats in each group. The rat model of sepsis was made by injecting LPS (10 mg/kg) into tail vein. The rats in sham group was given the same amount of normal saline (NS). After LPS injection, resveratrol (8 mg·kgn -1·dn -1) was intraperitoneally injected once daily for 2 days in the resveratrol group; the same amount of NS was given to the sepsis group and sham group. At 24 hours after model establishment, the cognitive function of the experimental rats was assessed by the Morris water maze test. The blood-brain barrier (BBB) permeability was evaluated by the brain water content (BWC) and Evans blue (EB) test. The protein expressions of matrix metalloproteinase 9 (MMP-9), Occludin and Claudin-5 in cortical tissue were detected by Western Blot. Double immunofluorescence was used to verify the co-localization of MMP-9 protein and the marker protein of astrocyte GFAP in the cortical tissue of rats.n Results:Compared with the sham group, the escape latency in the sepsis group was significantly longer [48-hour escape latency (s): 56.56±6.43 vs. 36.62±3.32, 72-hour escape latency (s): 57.72±7.23 vs. 26.46±4.24, both n P < 0.01], the BWC and extravasation of EB were increased [BWC: (84.56±2.03)% vs. (76.82±2.22)%, EB (μg/g): 17.56±2.28 vs. 6.25±1.36, both n P < 0.01], the expression of MMP-9 protein was increased (MMP-9/β-actin: 0.73±0.01 vs. 0.24±0.01, n P < 0.01), the protein expressions of Occludin and Claudin-5 were decreased (Occludin/β-actin: 0.45±0.02 vs. 0.86±0.04, Claudin-5/β-actin: 0.62±0.03 vs. 0.96±0.05, both n P < 0.01). At the same time, the co-localization expression of MMP-9 protein and the astrocytes of the cortical were increased [MMP-9 fluorescence intensity (AU): 38.66±4.26 vs. 17.23±3.04, MMP-9 positive cells: (26.92±1.77)% vs. (12.82±1.46)%, both n P < 0.01]. Compared with the sepsis group, the escape latency in resveratrol group was significantly shorter [48-hour escape latency (s): 41.42±6.27 vs. 56.56±6.43, 72-hour escape latency (s): 33.46±7.17 vs. 57.72±7.23, both n P < 0.01], the BWC and extravasation of EB were decreased [BWC: (77.15±2.27)% vs. (84.56±2.03)%, EB (μg/g): 7.74±1.88 vs. 17.56±2.28, both n P < 0.01], the expression of MMP-9 protein was decreased (MMP-9/β-actin: 0.25±0.01 vs. 0.73±0.01, n P < 0.01), the protein expressions of Occludin and Claudin-5 were increased (Occludin/β-actin: 0.82±0.03 vs. 0.45±0.02, Claudin-5/β-actin: 0.92±0.04 vs. 0.62±0.03, both n P < 0.01). At the same time, the co-localization expression of MMP-9 protein and the astrocytes of the cortical were decreased [MMP-9 fluorescence intensity (AU): 19.44±4.37 vs. 38.66±4.26, MMP-9 positive cells: (13.11±1.29)% vs. (26.92±1.77)%, both n P < 0.01].n Conclusion:Resveratrol can inhibit the expression of MMP-9 protein in the astrocytes of the cortical cortex of rats, and then reduce the degradation of tight junction proteins of Occludin and Claudin-5, thereby reducing BBB permeability and eventually ameliorate the cognitive dysfunction induced by SAE.