Ghrelin对大鼠急性胃粘膜损伤的保护作用

目的:研究Ghrelin对乙醇诱导的大鼠急性胃粘膜损伤的保护作用和可能机制。方法:大鼠随机分为4组:空白对照组、生理盐水组(NS组),0.5μg Ghrelin组(0.5μg GH组)和5μg Ghrelin组(5μg GH组)。75%乙醇灌胃建立急性胃粘膜损伤大鼠模型,NS组、0.5μg GH组和5μg GH组大鼠乙醇灌胃前1h分别给予NS、0.5μg Ghrelin和5μg Ghrelin腹腔注射。乙醇灌胃1h后处死大鼠,HE染色观察胃粘膜损伤程度并计算胃粘膜损伤指数,RT-PCR法检测胃粘膜环氧化酶-1(COX-1)和COX-2 mRNA的表达。结果:两个Ghrelin组大鼠胃粘膜损伤及炎症反应明显轻于NS组,各组大鼠胃粘膜COX-1 mRNA表达比较无统计学差异,两个Ghrelin组大鼠胃粘膜COX-2 mRNA的表达明显低于NS组,且呈量效关系(P<0.01,P<0.05)。结论:Ghrelin对乙醇诱导的大鼠急性胃粘膜损伤有明显的保护作用,其机制可能是抑制COX-2的过度表达。

PROTECTIVE EFFECTS OF GHRELIN ON ACUTE GASTRIC MUCOSAL LESION OF RATS

Objective:To study the protective effects of Ghrelin on ethanol-induced acute gastric mucosal lesion in rats and possible mechanisms.Methods:The rats were randomly divided into 4 groups: control group,physiological saline group(NS group),0.5μg Ghrelin group(0.5μg GH group) and 5μg Ghrelin group(5μg GH group).The acute gastric mucosal lesion rats model was established by lavaging of 75% ethanol.The rats in NS group,0.5μg GH group and 5μg GH group were intraperitoneally injected NS,0.5μg Ghrelin and 5μg Ghrelin respectively 1h before lavaging of 75% ethanol.HE stain was used to observe the degree of gastric mucosa injury and calculate gastric mucosa injury index;RT-PCR was used to detect cycloxygenase-1(COX-1) mRNA and COX-2 mRNA expression in gastric mucosa.Results:The gastric mucosa injury index and inflammatory reaction of rats in 2 Ghrelin groups were obviously lighter than NS group;There had no obvious differences about COX-1 mRNA expression in gastric mucosa of rats in each group;The COX-2 mRNA expression in gastric mucosa of rats in 2 Ghrelin groups was obviously lower than that in NS group(P<0.01,P<0.05),and showed dose-effect relationship.Conclusions:Ghrelin has obvious protective effects on ethanol-induced acute gastric mucosal lesion,and the possible mechanism maybe inhibiting expression of COX-2.