高三酰甘油血症对大鼠胰腺腺泡细胞凋亡的影响

目的:研究细胞凋亡在高三酰甘油(TG)血症损伤大鼠胰腺腺泡细胞中的作用.方法:断奶1周雄性SD大鼠(约70 g)随机分为两组,每组10只,分别给予高脂饲料和普通饲料喂养4周.检测血清TG和胆固醇(TC)水平.用胶原酶消化法分离大鼠胰腺腺泡细胞,用台盼兰染色测定细胞活力.给予不同浓度胆囊刺激素(CCK-8)刺激胰腺腺泡细胞,透射电镜下观察细胞超微结构变化,用RT-PCR方法检测细胞凋亡相关基因bax和bcl-2 mRNA的表达.结果:饲喂大鼠4周高脂饮食后血清TG较正常饮食组明显升高(P＜0.05).体外培养6 h后,高脂饮食组胰腺腺泡细胞活力低于对照组(P＜0.05).与CCK-8培养后,高脂组细胞发生明显病理损害,可见细胞凋亡和坏死表现.RT-PCR结果表明高脂组细胞与CCK-8共培养后,bax与bcl-2比值明显增高.结论:高TG血症可以加重大鼠胰腺腺泡细胞损伤,凋亡相关基因bax与bcl-2比值增高引起细胞凋亡可能参与其发病过程.

Effect of cell apoptosis on rat pancreatic acinar cells injury in dietary hypertriglyceridemia

Objective: To study the effect of cell apoptosis on rat pancreatic acinar cells injury in dietary hypertriglyceridemia. Methods: Male SD rats were assigned to one of two experimental groups and fed for 4 weeks with high fat diet or normal diet. Blood samples were taken to measure triglyceride and cholesterol in plasma. Pancreatic acinar cells were isolated by collagenase digestion. Cell viability was determined by typan blue dyeing at different time points. Cells treated with CCK-8 were examined under transmission electron microscope. Expressions of bax and bcl-2 were investigated by RT-PCR. Results: Compared with the normal diet group, the level of triglyceride was increased significantly in high fat diet group(P<0.05). Cell mortality obviously increased after 6 h of isolation in high diet group (P<0.05). Enzyme vacuoles were observed in cells of normal fat diet group treated with 10pmol/L CCK-8. Cell apoptosis, necrosis and decreased density of intracellular zymogen granules were observed in both groups with 10nmol/L CCK-8 and in high fat diet group with 10pmol/L CCK-8. The ratio of bax to bcl-2 mRNA was significantly higher in high fat diet group(P<0.05). Conclusions: The present results indicate high fat diet can induce hypertriglyceridemia in rat and increased triglyceride can injure the pancreatic acinar cells. Pancreatic acinar cells apoptosis and elevated ratio of bax to bcl-2 may play an important role.