异丙酚对大鼠内毒素脑损伤STAT3表达的影响

目的 研究异丙酚对大鼠内毒素脑损伤中信号转导子与转录激活子-3( STAT3)表达的影响,探讨异丙酚在脑损伤中的保护作用及其机制.方法 健康清洁级SD大鼠72只,雌雄不限,体重220～ 250 g,随机分为3组(n=24):L组(内毒素组)和LP组(内毒素+异丙酚组)经颈内动脉注射内毒素200 μg建立大鼠内毒素脑损伤模型,C组(对照组)经颈内动脉注射等量生理盐水,LP组颈内动脉注射内毒素后即予异丙酚100 mg/kg剂量腹腔注射.3组分别于6、12、24和48h随机处死6只大鼠,取额叶皮质,检测脑组织含水量,免疫组织化学检测P-STAT3、NF-κB和iNOS表达水平的变化,Western blot法检测大鼠内毒素脑损伤后P-STAT3蛋白表达水平的变化.结果 与C组相比,L组、LP组各时间点脑组织含水量、P-STAT3、NF-κB和iNOS表达增加(P ＜0.05,P＜0.01);与L组比较,LP组各时间点脑含水量、P-STAT3、NF-κB和iNOS表达明显减少(P＜0.05,P＜0.01).结论 异丙酚可减轻大鼠内毒素性脑损伤,机制可能与抑制脑组织磷酸化STAT3、NF-κB和iNOS表达水平上调,进而减轻炎性反应有关.

Effects of Propofol Treatment on Expression of STAT3 in Brain Tissue in Rats with LPS-induced Brain Injury

Objective To investigate the effects of propofol treatment on expression of P-STAT3 and cell apoptosis in brain tissue in rats with LPS-induced brain injury. Methods Seventy two male and female SD rats weighting 220-250g were randomly divided into 3 groups（ n = 32 each） ：Cerebral edema was induced by injecting LPS 200μg via left internal carotid artery in group L and group LP. In control group（ group C ） ,equal volume of nomad saline was administered iv instead of LPS. Group LP received intraperitoneal Propofol 100mg/kg immediately after LPS administration. Six rats of each group were decapitated at 6,12 ,24 and 48h after operation and their frontal lobe cortex were immediately removed for determination of water content of brain, the expression of P-STAT3 ,NF-κB and iNOS proteins were detected by immunohistochemistry, and the Western blot analysis were used to detect the expression of P-STAT3 proteins. Results In group L and group LP the brain water content, the number of neuronal apoptosis increased, the expression of P-STAT3 ,NF-κB and iNOS proteins were significantly increased compared with group C （ P 〈 0. 05, P 〈 0.01 ）. In group LP these results were markedly reduce compared with group L（ P 〈 0. 05, P 〈 0.01 ）. Conclusion Propofol can attenuate LPS-induced brain injury,it might be related to the decrease of P-STAT3 ,NF-κB and iNOS protein expression.