Ghrelin对CKD大鼠十二指肠消化间期移行性复合运动和Bcl-2/Bax表达的影响

摘要

Objective To observe the effect of ghrelin on interdigestive migrating motor complex (MMC) and Bcl-2/Bax expression in the duodenum of chronic kidney dysfunction (CKD) rats. Methods Totally 18 SD rats weighing (180±20)g were randomly divided into control group, ghrelin group 1 (CKD+ghrelin 10 μg/kg) and ghrelin group 2 (CKD + ghrelin 50 μg/kg), with 6 in each group. CKD rat model was set up in the latter two groups using 5/6 nephrectomy technique, then immunohistochemical staining was employed to detect the expressions of Bcl-2 and Bax in the duodenum, and multi-channel physical recorder machine was employed to recorder MMC of the duodenum. Results The rats with CKD had disorder of motility in the duodenum. In control group, ghrelin group 1 and ghrelin group 2, ghrelin could significantly improve the time [(0.81 + 0.12)min vs. (0. 84 + 0.13)min vs. (0.99 + 0. 17)min], frequency [(22. 68+1.00)min vs. (23. 55± 1. 08)min vs. (29. 31 + 1. 51 )min] and amplitude [(249.71±13.98)μV vs. (258. 49+ 13. 12) μV vs. (318. 85 + 20. 10)μV] of phase Ⅲ in MMC of the duodenum (P<0.05). Meanwhile, ghrelin down-regulated the expressions of Bcl-2 and Bax, especially that of Bax ( P < 0.05), and then increased the ratio of Bcl-2/Bax (P<0.05). Conclusion Ghrelin can obviously improve motor function of CKD rat duodenum; therefore, it may be a new prokenetic drug.%目的 观察ghrelin对慢性肾功能不全(CKD)大鼠十二指肠消化间期移行性复合运动变化和Bcl-2/Bax表达的影响.方法 SD大鼠18只,体重(180±20)g,雌雄不拘,随机分为对照组(CKD+生理盐水)、ghrelin 1组(CKD+ghrelin 10μg/kg)和ghrelin 2组(CKD+ghrelin 50μg/kg),每组6只.采用5/6肾切除法建立CKD大鼠模型.模型建立成功后分别采用多道生理记录仪和免疫组织化学方法观察十二指肠消化间期移行性复合运动变化和凋亡相关基因Bcl-2/Bax的表达.结果 CKD大鼠普遍存在十二指肠运动功能障碍；ghrelin可以明显增加CKD大鼠十二指肠消化间期移行性复合运动出现的频率,包括呈剂量依赖性增加Ⅲ相出现的时间、频率和振幅,各参数在对照组、ghrelin 1组和ghrelin 2组分别为:Ⅲ相出现的时间[(0.81±0.12)minvs.(0.84±0.13)min vs.(0.99±0.17)min];频率[(22.68±1.00)次/min vs.(23.55±1.08)次/min vs.(29.31±1.51)次/min]；振幅[(249.71±13.98)μV vs.(258.49±13.12)μV vs.(318.85±20.10)μV] (P＜0.05).同时ghrelin可以明显减少Bcl-2和Bax的表达,其中以Bax的减少更明显(P＜0.05),Bc1-2/Bax比值增加(P＜0.05).结论 ghrelin可以明显改善CKD大鼠十二指肠的运动功能,有可能成为一种新型胃肠动力药物.