糖尿病大鼠胃窦平滑肌细胞Ryanodine受体表达变化的研究

Study of the Ryanodine receptor in smooth muscle cells in gastric antrum of diabetic rats

目的探讨糖尿病大鼠胃窦平滑肌Ryanodine受体(RyR)的改变及其意义。方法 Wistar大鼠50只,随机分为糖尿病组和对照组,用链尿佐菌素建立大鼠糖尿病模型,3个月后测定胃排空时间,用激光共聚焦方法测定胃窦平滑肌细胞内Ca2+浓度,Western blot法检测胃窦平滑肌组织RyR蛋白变化。结果与对照组大鼠相比,糖尿病组大鼠胃排空时间明显延长(P<0.05),平滑肌细胞内Ca2+浓度明显增加(P<0.05),而胃窦平滑肌组织RyR蛋白表达明显减少(P<0.05)。结论糖尿病大鼠胃窦平滑肌RyR受损,从而导致细胞内Ca2+信号调控异常致使平滑肌功能异常是糖尿病胃肠道功能障碍重要因素之一。

Objective To study the change of ryanodine receptor（RyR） in gastric antrum of diabetic rat.Methods 50 rats were randomly divided into diabetic group and control group.Gastric empty time was determined 3 months after diabetes reproduced in rats,the content of cytosolic Ca2＋ in smooth muscle cells was measured by laser scanning confocal microscopy and the expressions of RyR in smooth muscle of diabetic rats were measured with Western blot method.Results In diabetic rats,gastric emptying was significantly delayed（P0.05）.Compared the normal rats,the content of cytosolic Ca2＋ in smooth muscle cells from the antrum of diabetic rats was increased and the expression of RyR in muscular layer in diabetic rats was significantly down-regulated（P0.05）.Conclusion Down-regulation of RyR induces abnormality of cytosolic Ca2＋ in gastric antral smooth muscle in diabetic rats and then leads to gastric motility disorder.