生长抑素对急性胰腺炎胰腺细胞凋亡作用机制的初步研究

Effects and mechanisms of somatostatin on apoptosis of pancreatic acinar cells in acute pancreatitis of mice.

目的 探讨生长抑素治疗小鼠急性胰腺炎对胰腺细胞凋亡及凋亡调控基因ｐ５３ 、ｂａｘ 的影响。方法 以蛙皮素诱导ＣＤ１ 小鼠急性胰腺炎模型，并应用ＴＵＮＥＬ 染色、免疫组化ＳＰ技术等检测胰腺细胞凋亡及凋亡调控基因ｐ５３ 、ｂａｘ 的蛋白表达以及生长抑素治疗后对胰腺细胞凋亡及凋亡调控基因ｐ５３ 、ｂａｘ 蛋白表达的影响。结果 苏木精伊红染色观察到胰腺组织中典型的细胞凋亡形态学特征：细胞核固缩及凋亡小体形成。ＴＵＮＥＬ结果显示蛙皮素组、正常组胰腺细胞凋亡指数显著低于生长抑素治疗组。免疫组化显示正常胰腺组织未见凋亡调控基因ｐ５３ 、ｂａｘ 的表达，生长抑素治疗组胰腺细胞ｐ５３ 染色阳性率明显高于蛙皮素组，而ｂａｘ 染色阳性率虽高于蛙皮素组，但无统计学意义。结论 生长抑素治疗急性胰腺炎的机制之一可能是诱导损伤的胰腺细胞凋亡以减轻炎症反应，该细胞凋亡机制可能与凋亡调控基因ｐ５３ 的表达有关而与ｂａｘ 的表达无关。

Objective To investigate the effects of somatostatin on apoptosis of pancreatic acinar cells and apoptosis regulatory gene p53 and bax in treating acute pancreatitis of mice. Methods In cerulein induced pancreatitis with or without treatment of somatostatin of CD 1 mice, apoptosis of pancreatic acinar cells was detected by TUNEL method, and the expression of apoptosis regulatory gene p53 and bax were determined by SP immunohistochemical technique.Results On the H&E staining, acinar cells in the pancreas showed pyknotic nuclei and formation of apoptotic bodies, which were the typical morphological features of apoptosis. On TUNEL, the apoptotic indices of pancreatic acinar cells in cerulein group and control group were significantly lower than that of somatostatin treated group, respectively. On immunohistochemistry, there was no positive staining cells in normal pancreatic tissues. The postive rate of p53 in somatostatin treated group was markedly higher than that of cerulein group, but there was no marked difference on the positive rate of bax between somatostatin treated group and cerulein group.Conclusion Induction of apoptosis in pancreatic acinar cells injury might be one of the mechanisms of somatostatin in treating acute pancreatitis in mice, and the mechanisms of apoptosis might be correlated with the expression of apoptosis regulatory gene p53 but has no relations with the expression of bax.(Shanghai Med J, 2000,23∶67 69)