糖尿病结肠动力障碍与几种胃肠激素变化的意义

Research on neuroendocrine peptides and gastrointestinal dysmotility in diabetes mellitus

目的 研究糖尿病大鼠模型离体近端结肠平滑肌的收缩运动 ,及其与血浆和结肠组织中生长抑素 (SS)、血管活性肠肽 (VIP)、胃动素 (MTL)、P物质 (SP)在糖尿病结肠动力障碍中的作用。方法 建立糖尿病大鼠模型 ,制备试验组和对照组大鼠离体近端结肠环行肌及纵行肌肌条 ,应用张力换能器测定其静息张力、平均振幅、收缩频率等运动指标 ;用放免法同批测定两组大鼠血浆和近端结肠组织中SS、VIP、MTL和SP含量。结果 (1)糖尿病组结肠肌条收缩运动的多项指标均较对照组明显降低 (P <0 0 1) ;(2 )糖尿病组血浆中SS、VIP、MTL增加 ,SP降低 ,结肠组织中SS和VIP降低 ,SP增加 ,MTL无变化 ;(3)血浆和肠组织SS与结肠运动指标无显著相关 ;血浆VIP和MTL与结肠运动呈负相关 ,而组织中VIP与结肠运动呈正相关 ;血浆SP和结肠运动呈正相关。结论 (1)糖尿病多伴有结肠运动功能障碍 ;(2 )

Objective To investigate the relationship between contractive activity of isolated proximal colon smooth muscle and the change of somatostatin(SS),vasoactive intestinal peptide(VIP),motilin(MTL),substance P(SP) in diabetes mellitus rats.Methods Twenty male Sprague-Dawley rats were divided into two groups:the control(n=10) and the experimental(n=10).The resting tension,the mean contractile amplitude and frequency of spontaneous changes of isolated longitudinal,circular proximal colon smooth muscle strips were measured by transducer,and SS,VIP,MTL,SP levels in plasma and proximal colon tissue extracts were measured by radioimmunoassay.Results (1)In isolated colon smooth muscle strips,the motility parameters were significantly lower in diabetic rats than those in control(P<0.01).(2)In diabetic rats,the plasma levels of SS,VIP and MTL were higher than those in control(P<0.05),while SP level was decreased(P<0.05).In the proximal colon,the levels of SS,VIP were significantly lower than in the control(P<0.05),the level of SP was higher than that of the control(P<0.05),and the level of MTL did not differ from that in the lean control(P>0.05).(3)In diabetic rats,there was no excellent correlation between the plasma,tissue SS levels and the motility parameters of colon,and the plasma VIP and MTL had a negative correlation with the motility parameters of colon,but the VIP level of proximal colon had a positive correlation with colon motility parameters.The plasma SP level had a positive correlation with colon motility.Conclusions (1)Diabetic rats have colonic dysfunction and it is related with the disturbed neuroendocrine peptides.(2)The changes of these peptideslevels in plasma and colon tissue may play some role in the gastrointestinal disorders of diabetes mellitus.