链脲佐菌素致大鼠Ⅰ型糖尿病后的肠微循环表现

Intestinal Microcirculation Manifestations in Rats with Type I Diabetes Mellitus

目的:研究链脲佐菌素(streptozocin, STZ)所致Ⅰ型糖尿病大鼠肠系膜淋巴管收缩性情况,以及肠管血流灌注情况。方法:将健康SPF级12周龄成年Wistar大鼠16只,体重为190~220 g,随机分为正常组和Ⅰ型糖尿病组,腹腔注射STZ制备Ⅰ型糖尿病大鼠模型。一周后,利用激光散点动态血流监测系统(PeriCam PSI)观察大鼠肠管血流灌注量,利用动态可视化微循环研究系统(Gene&Ⅰ)观察大鼠肠系膜淋巴管收缩性,测量肠组织湿干比用以明确水肿情况。结果:糖尿病组大鼠的肠管血液灌注量相比正常组大鼠的肠管血液灌注量有着明显的提高(243.21±9.19 vs 199.33±10.33,P<0.05),同时其肠组织湿干比也有明显提高(5.10±0.09 vs 4.43±0.08,P<0.05),Ⅰ型糖尿病大鼠肠系膜淋巴管的收缩性无显著性变化(P>0.05),IndexⅠ收缩分数、IndexⅡ总收缩活性指数和L.D-Index肠系膜淋巴管动力学指数无统计学差异。结论:STZ诱导Ⅰ型糖尿病一周后会导致大鼠的肠道发生组织水肿,肠管血液灌注量增加,而对肠系膜淋巴管收缩性影响不大。

Objective:To study themesenteric lymphatic contractility and intestinal blood perfusion in rats with type I diabetes mellitus caused by streptozocin(STZ).Methods:SPF Wistar rats(12-week-old)weighing 190~220 g,16 animals were randomly divided into control group and type I diabetes group.STZ was injected intraperitoneally to induce type I diabetes.One week later,the intestinal blood perfusion was observed by PeriCam PSI System,which is a blood perfusion imager based on the laser speckle contrast analysis(LASCA)technology.The mesenteric lymphatic contractility of rats was observed by dynamic visualization microcirculation research system(Gene&.I).The wet-dry ratios of intestinal tissues were measured to estimate the edema condition.Results:Compared with that of normal rats,the intestinal blood perfusion of diabetic rats was significantly increased(243.21±9.19 vs 199.33±10.33,P<0.05).Meanwhile,the wet-dry ratio of intestinal tissues was also significantly elevated(5.10±0.09 vs 4.43±0.08,P<0.05)in the type I diabetes group.Whereras,the contractility of mesenteric lymphatic vessels in the diabetic rats was comparable with that in the control group(P>0.05),evidenced by comparable lymphatic fractional contraction(Index I),overall lymphatic contractile activity(Index II)and peristalsis dynamics of lymphatic vessel(L.D-Index).Conclusion:One week after STZ induction,the rats with type I diabetes showed increased intestinal edema and increased intestinal blood perfusion,but the mesenteric lymphatic contractility was not affected.