摘要
目的研究雷帕霉素(rapamycin,RAPA)对实验大鼠胰性脑组织损害是否具有保护作用及其可能的机制。方法采用随机数字表法选取清洁级雄性SD大鼠90只,拆信封法随机均分成3组,即假手术(sham operation,SO)组、重症急性胰腺炎(severe acute pancreatitis,SAP)组和RAPA组,每组再用随机数字表法随机均分为24 h、36 h和48 h 3个亚组。3组大鼠均经开腹逆行胰胆管注射药液构建SAP模型,SO组注射0.9%生理盐水(2 mL/kg),SAP组和RAPA组均注射5%牛磺胆酸钠(2 mL/kg),但RAPA组在麻醉前30 min经腹腔注射RAPA(1 mg/kg),3组大鼠分别于注射药物后24 h、36 h和48 h处死相应亚组存活的全部大鼠,收取大鼠胰腺组织和脑组织,行苏木精-伊红染色;脑组织另行卢卡斯快蓝染色,光镜下对脑组织的病理学改变进行评分,通过比较3组大鼠脑组织损害程度的差异以明确RAPA对胰性脑组织损害是否具有保护作用。采用蛋白印迹法检测脑组织中磷酸化哺乳动物雷帕霉素靶蛋白(phosphorylated mammalian target of rapamycin,p-mTOR)和磷酸化核糖体40S小亚基S6蛋白激酶(phosphorylated ribosomal 40S small subunit S6 protein kinase,p-S6K1)的表达水平,并对脑组织中p-mTOR和p-S6K1的表达水平与脑组织损害程度进行相关性分析,进一步探索RAPA对SAP脑组织损害具有保护作用的可能机制。结果①脑组织中p-mTOR和p-S6K1的相对表达水平在24 h、36 h及48 h时点均是SO组<RAPA组<SAP组(P<0.05);②脑组织病理学评分在24 h、36 h及48 h时点均是SO组<RAPA组<SAP组(P<0.05);③脑组织中p-mTOR和p-S6K1的相对表达水平与脑组织的病理学评分均呈正相关关系(r=0.99,P<0.01;r=0.97,P<0.01)。结论RAPA通过下调mTOR信号通路中p-mTOR和p-S6K1的表达量对胰性脑组织损害发挥保护作用。
Objective To explore the protective effect of rapamycin on brain tissues injury in severe acute pancreatitis(SAP)and its possible mechanism in experimental rats.Methods Ninety SPF males SD rats were randomly divided into 3 groups by random envelope opening method:sham operation group(SO group),SAP group,and rapamycin group(RAPA group),then the rats of each group were divided into 24 h,36 h,and 48 h 3 subgroups by random number table method.Rats in each group underwent laparotomy,the model was prepared by retrograde injection of solutions into biliopancreatic duct,rat of the SO group was injected with 0.9%normal saline(2 mL/kg),rats of the SAP group and the RAPA group were injected with 5%sodium taurocholate solution(2 mL/kg),but rat of the RAPA group was injected with rapamycin(1 mg/kg)at 30 min before narcosis.All survival rats in each subgroup were killed at 24 h,36 h,and 48 h respectively,then the pancreas and brain tissues of rats were collected,pancreas and brain tissues were stained by hematoxylin-eosin staining,brain tissues were stained by Luxol fast blue additionally,pathological changes of brain tissues were scored under light microscope.The protective effect of rapamycin on brain tissues injury was determined by comparing the differences in the degree of brain tissues among 3 groups.The phosphorylated mammalian target of rapamycin(p-mTOR)and phosphorylated ribosomal 40S small subunit S6 protein kinase(p-S6K1)expression levels in brain tissues were detected by Western blot.In addition,the correlations between the expression levels of p-mTOR and p-S6K1 in brain tissues and the degree of brain tissues injury were analyzed to further explore the possible mechanism of rapamycin’s protective effect on brain tissues injury in SAP.Results①At the point of 24 h,36 h,and 48 h,the order of the relative expression levels of p-mTOR and p-S6K1 in brain tissues of three groups were all as follows:the SO group<the RAPA group<the SAP group(P<0.05).②At the point of 24 h,36 h,and 48 h,the order of brain histological
作者
吉九威
宋卫东
赵海平
JI Jiuwei;SONG Weidong;ZHAO Haiping(Department B of Abdominal Surgery,The Affiliated People’s Hospital of Inner Mongolia Medical University(Inner Mongolia Autonomous Region Cancer Hospital),Hohhot 010010,P.R.China)
出处
《中国普外基础与临床杂志》
CAS
2022年第7期869-874,共6页
Chinese Journal of Bases and Clinics In General Surgery
