急性胰腺炎胰酶胞内激活机制中Cpn60的可能作用

Cpn60 deficiency may play a role in the intrapancreatic enzyme activation in acute pancreatitis

目的 :进一步探讨急性胰腺炎 (AP)时胰酶胞内激活的机制及蛋白伴侣因子 (Cpn6 0 )在其中的可能作用。方法 :用去氧胆酸钠逆行注入大鼠胰胆管复制AP模型 ,5h、10h分批采血、取胰腺 ,测血清及胰腺组织中淀粉酶活性及炎症介质TNF -α的含量 ;取 5h胰腺作光镜、电镜切片 ,检测胰腺组织和腺泡细胞各细胞器形态学的变化 ;用蛋白金标免疫细胞化学技术检测各细胞器中Cpn6 0及胰酶含量的变化。结果 :血清淀粉酶活性及胰腺组织匀浆TNF-α含量在 5h明显高于正常对照组 ,持续达 10h ;AP 5h的光镜病理检查见胰腺水肿、出血、坏死 ;电镜检查见腺泡内溶酶体增多 ,形态各异 ,散在于各处 ,甚至位于高尔基体中 ;内质网、高尔基体、酶原颗粒等细胞器中Cpn6 0明显减少 ,然而胰脂肪酶含量升高 ,糜蛋白酶原保持在高浓度水平。结论 :AP时腺泡细胞内溶酶体增多 ,分布异常 ,尤其胰脂肪酶以及蛋白酶含量增多 ,Cpn6 0含量减少 ,提示蛋白伴侣相对不足 ,这些异常变化可能引起胰酶在腺泡内的聚积和激活 ,从而参与AP的发生和发展。

AIM: To investigate the change of Cpn60 content,the alterations of pancreatic enzymes and lysosome,in order to better understand the mechanism of intrapancreatic enzyme activation in acute pancreatitis(AP). METHODS: The AP model was replicated by retrograde infusion of 4% sodium-deoxycholate in the choledocus of SD rats. The levels of amylase in plasma and TNF-α in pancreatic tissue were measured by biochemical technique at 5 h and 10 h after AP induction. The content of Cpn60 and pancreatic enzymes in different compartments of the acinar cells were tested by quantitative protein A-gold immunocytochemistry technique. The change of lysosome in the acinar cells was observed under the electronic microscope. RESULTS: After AP was induced,the levels of amylase in the plasma and TNF-α in the pancreatic tissue increased significantly. Lysosomes with different forms were found inside the acinar cells,and some of them located in the Golgi apparatus. Cpn60 content decreased,which was accompanied by an increase of lipase or chymotrypsinogen content in the pancreatic secretory pathway. CONCLUSION: In the pancreatic acinar cells of AP rats,Cpn60 content decreased,suggesting an insufficient chaperone capacity,and combining with the change of lysosome both in its amount and location,which may take part in the intrapancreatic enzyme activation and the development of AP.