高血糖大鼠血浆胃促生长素及肥胖抑制素水平与胃排空的相关性探讨

Investigation on the correlations between gastric emptying and level of plasma ghrelin and obestatin in diabetic rats

目的探讨糖尿病初期血浆胃促生长素、肥胖抑制素及其比值(G/O)对胃排空的影响。方法将60只清洁级雄性W istar大鼠随机分为对照组(NC组)、糖尿病组(DM组)、胰岛素干预组(INS组)各20只。后两组腹腔注射链脲佐菌素(STZ)制备糖尿病模型。INS组每日皮下注射中效胰岛素,另两组皮下注射生理盐水。分别于制模2周、6周,每组随机取半数进行实验,以酚红灌胃法检测胃排空率,酶免疫分析法检测血浆胃促生长素、肥胖抑制素水平。结果2周后,DM组较NC组胃排空率升高(P<0.001),胃促生长素、肥胖抑制素水平增高(P<0.01),G/O值略增高;INS组大鼠胃排空率低于DM组(P<0.001),G/O值低于DM组及NC组(P<0.01)。6周后,DM组较NC组胃排空率升高(P<0.001),胃促生长素、肥胖抑制素水平增高(P<0.01),G/O值增高(P<0.05);INS组较DM组胃排空减慢(P<0.001),血浆肥胖抑制素升高(P<0.05)。结论糖尿病初期血浆G/O升高是胃排空加快的可能原因之一,外源性补充胰岛素对肥胖抑制素水平的影响可能与调节胃排空有一定关系。

Objective To investigate the effects of plasma ghrelin, obestatin and ghrelin/obestatin （G/O） on the gastric emptying in early stage of diabetes mellitus. Methods Sixty male Wistar rats were randomly divided into normal control group（ NC group） , diabetes mellitus group（ DM group） , insulin-treated group（ INS group） with 20 in each. The in- traperltoneal injection of streptozotocin （STZ） was used to induce diabetic models in the later two groups. INS group was given intermediate-acting insulin by hypodermic injection every day, and the other two groups were given normal saline. Two and six weeks after the injection, half of each group was taken out for experimentation. The gastric emptying was measured by intragastrie administration of phenol red ,the plasma ghrelin and obestatin were detected by enzyme immunoassay. Results Two weeks later, the gastric emptying and level of plasma ghrelin and obestatin in DM group increased compared with those in NC group（P 〈0. 001,0.01,0.01 ） , and G/O was a little higher than that in NC group. The gastric emptying and G/O in INS group decreased compared with those in DM group（P 〈0.01 ）. Six weeks later, the gastric emptying and level of plasma ghrelin and obestatin in DM group increased eompared with those in NC group（ P ,〈 0. 001,0.01,0.01 ） , and G/O was higher than that in NC group （ P 〈 0.05）. The gastric emptying in INS group decreasGd compared with that in DM group （ P 〈 0.01 ）, the level of plasma obestatin increased （ P 〈 0.05 ）. Conclusions In early stage of diabetes mellitus, the increase of plasma G/O may be one of the important factors for the promotion of gastric emptying. The effect of extrinsic insulin on plasma obcstatin may be related to the regulation of gastric emptying.