严重烫伤大鼠早期胰岛素分泌功能变化及信号转导机制  

Changes of insulin secretion and its signal transduction mechanism at early stage of severe scald in rats

作　　者：张博涵 申传安[1] 孙鹏超 郑波 李大伟[1] 刘兆兴 徐圣博 孙佳辰 张文[1] Zhang Bohan;Shen Chuan′an;Sun Pengchao;Zheng Bo;Li Dawei;Liu Zhaoxing;Xu Shengbo;Sun Jiachen;Zhang Wen(Department of Burns and Plastic Surgery,the Fourth Medical Center of PLA General Hospital,Beijing 100048,China)

机构地区：[1]解放军总医院第四医学中心烧伤整形科,北京100048

出　　处：《中华烧伤杂志》2020年第4期280-287,共8页Chinese Journal of Burns

基　　金：国家重点研发计划重点专项(2017YFC1103503);国家自然科学基金面上项目(81373140);北京市自然科学基金重点项目(7171009);北京市科技计划"首都临床特色应用研究与成果推广"(Z171100001017146)。

摘　　要：目的观察严重烫伤大鼠早期胰岛素分泌功能变化情况并探讨其信号转导机制。方法将24只7周龄雄性Wistar大鼠按随机数字表法分为单纯假伤组、假伤+BPV(HOpic)组、单纯烫伤组和烫伤+BPV(HOpic)组,每组6只。单纯烫伤组、烫伤+BPV(HOpic)组大鼠在94℃热水中浸浴腹部6 s、背部12 s,造成50%体表总面积Ⅲ度烫伤;单纯假伤组、假伤+BPV(HOpic)组大鼠在37℃温水中浸浴腹部6 s、背部12 s,模拟致伤。伤后0(即刻)~2 d,烫伤+BPV(HOpic)组、假伤+BPV(HOpic)组大鼠每天一次性腹腔注射0.5 mg/mL磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/Akt)信号通路增强剂BPV(HOpic)溶液0.6 mg/kg,单纯烫伤组、单纯假伤组大鼠每天一次性腹腔注射等体积二甲基亚砜。伤后72 h,剪尾法取大鼠尾血,用血糖仪测定空腹血糖;取大鼠胰腺组织,苏木精-伊红染色观察胰岛组织病理学表现,透射电镜观察胰岛β细胞超微结构以计数每10微米细胞膜上锚接胰岛素颗粒并计算胰岛素空泡占比,蛋白质印迹法检测胰腺PI3K/Akt信号通路中Akt磷酸化水平。对数据行单因素方差分析和LSD检验。结果(1)伤后72 h,单纯假伤组与假伤+BPV(HOpic)组大鼠空腹血糖水平均正常且相近(P>0.05),与该2组比较,单纯烫伤组大鼠空腹血糖水平显著升高(P<0.01),烫伤+BPV(HOpic)组大鼠空腹血糖水平没有明显变化(P>0.05)。与单纯烫伤组比较,烫伤+BPV(HOpic)组大鼠空腹血糖水平显著降低(P<0.01)。(2)伤后72 h,单纯假伤组与假伤+BPV(HOpic)组大鼠胰岛形态完整且胰岛细胞排列整齐,与该2组比较,单纯烫伤组大鼠胰岛形态不完整,胰岛内空泡样变多见,细胞排列不规则,部分胰岛β细胞胞质淡染或透亮;烫伤+BPV(HOpic)组大鼠胰岛形态变化不明显。与单纯烫伤组比较,烫伤+BPV(HOpic)组大鼠胰岛形状较为完整,胰岛内空泡样变较少,细胞排列较规则,胰岛β细胞胞质淡染或透亮较少。(3)伤后72 h,单纯假伤组与假Objective To observe the changes of insulin secretion in the early stage of severe scald in rats,and to explore its signal transduction mechanism.Methods Twenty-four male Wistar rats aged 7 weeks were divided into sham injury alone(SIA)group,sham injury+BPV(HOpic)(SIB)group,scald alone(SA)group,and scald+BPV(HOpic)(SB)group using the random number table,with 6 rats in each group.Full-thickness scald of 50%total body surface area was inflicted in rats of SA and SB groups by a 6-s immersion of the abdomen and a 12-s immersion of the back in 94℃hot water.Rats in SIA and SIB groups received sham injuries through immersion of the back and abdomen in 37℃warm water for 6 and 12 seconds respectively.From 0(immediately)to 2 day(s)after injury,the rats in groups SB and SIB were intraperitoneally injected with the phosphatidylinositol 3-kinase/protein kinase B(PI3K/Akt)signaling pathway enhancer BPV(HOpic)solution(0.5 mg/mL)at the dosage of 0.6 mg/kg once a day,and the rats in groups SA and SIA were intraperitoneally injected with the same volume of dimethyl sulfoxide once a day.At post injury hour(PIH)72,the tail blood of rats was sampled for measuring fasting blood glucose(FBG)with a glucometer,and the pancreatic tissue samples of rats was harvested for observing the pathological manifestations of islets by hematoxylin-eosin staining,counting the docked granules per 10μm membrane of islet beta cells and calculating the proportion of insulin vesicles through the observation of the ultrastructure of islet beta cells by transmission electron microscope,and detecting the phosphorylation level of Akt in the pancreatic PI3K/Akt signaling pathway by Western blotting.Data were statistically analyzed with one-way analysis of variance and least significant difference test.Results(1)At PIH 72,the rat FBG levels in SIA and SIB groups were normal and similar(P>0.05).Compared with the levels of those two groups,the rat FBG level in SA group was increased significantly(P<0.01),while the level in SB group showed no obvious change(P>

关 键 词：烧伤 胰岛素 胰腺 血糖 磷脂酰肌醇3-激酶/蛋白激酶B信号通路 BPV(HOpic) 

分 类 号：R619+.6[医药卫生—外科学] R329.2[医药卫生—临床医学]