Ghrelin对肾功能不全大鼠胃肠移行性复合运动的影响

摘要

目的 探讨ghrelin对肾功能不全(CRF)大鼠胃肠移行性复合运动(MMC)的影响.方法 健康雄性SD大鼠30只,随机取出6只做假手术组,其余24只根据是否预先应用ghrelin受体GHS-R的抑制剂D-Lys3-GHRP-6以及ghrelin剂量不同而分为ghrelin 1～4组.采用5/6肾切除法建立CRF大鼠模型.采用多道生理记录仪在大鼠清醒、禁食状态下监测消化间期MMC,观察腹腔注射不同剂量ghrelin对MMC周期的影响,以及给予D-Lys3-GHRP-6对ghrelin作用的影响.结果 慢性肾功能不全大鼠存在胃肠动力障碍,表现为胃肠道形态异常的MMC增加,MMC周期缩短,频率增加,Ⅲ相振幅减低;ghrelin可以明显增加MMC出现的频率、增加Ⅲ相出现的时间、频率和振幅,且呈剂量依赖性(P＜0.05);D-Lys3-GHRP-6可以抑制ghrelin的作用.结论 ghrelin可以明显改善CRF大鼠MMC周期紊乱,进而改善其胃肠动力障碍.%Objective To investigate the effect of ghrelin on deodunal migrating myoelectric complex (MMC) in rats with chronic renal failure (CRF). Methods Thirty healthy male SD rats were randomly assigned into sham-operated group (n=6) and CRF group (n=24), and the latter group was divided into 4 subgroups according to ghrelin doses administered with or without pretreatment with the receptor antagonist D-Lys3-GHRP-6. After a 18-h fasting, the rats with or without pretreatment with D-Lys3-GHRP-6 were given subcutaneous injections of ghrelin at different doses to observe the changes in deodunal MMC recorded using a multilead physiological recording system. Results Ghrelin significantly increased the MMC cycle duration and dose-dependently enhanced the frequency, amplitude and percentage of phase HI MMC cycle. This effect was inhibited by the pretreatment with ghrelin receptor antagonist D-Lys3-GHRP-6. Conclusion Ghrelin can promote gastrointestinal motilities of rats with CRF, and the receptor of ghrelin can regulate the activity of MMC.