糖尿病大鼠腹主动脉零应力状态

ZERO-STATE OF ABDOMINAL AORTA IN DIABETIC RATS

目的 通过腹主动脉零应力状态的研究 ,探讨糖尿病、高血压大鼠血管力学特性重建的规律。方法 用链脲佐菌素 (STZ)分别诱导SD和自发性高血压大鼠 (SHR) ,建立伴有高血压的糖尿病(SHRDM)和不伴有高血压的糖尿病 (SDDM)动物模型 ,利用生物显微镜和图像分析系统对其腹主动脉张开角进行观测。结果 ( 1 )SD组大鼠主动脉张开角在病程 1周到 4周加大 ,其后缓慢减小 ,8周后趋于平稳。 ( 2 )SDDM组大鼠主动脉张开角 1～ 4周急剧升高 ,4～ 8周急剧降低 ,1 6周后又急剧升高。 8周、1 6周时SDDM小于SD(P <0 .0 5 ) ,4周和 2 4周时SDDM大于SD(P <0 .0 1 ) 。 ( 3)SHR张开角的变化趋势恰与SDDM相反 ,且在 1周、8周、1 6周时大于SD (P <0 .0 1 ) ,而 4周时又小于SD (P <0 .0 1 ) 。( 4)SHRDM张开角的变化与SDDM趋势相似 ,但 4周时小于SDDM (P <0 .0 1 ) ,8、1 6周时大于SDDM(P <0 .0 5 ) 。结论 糖尿病、高血压大鼠主动脉壁零应力状态异常 ,在病程早期两者的变化趋势相反 ,提示高血压和糖尿病大血管壁均存在明显的不均匀生长 ,但是不均匀性生长的方式不同。

Objective To reveal the rule of the biomechanical remodeling of the aorta by studying zero?stress state of abdominal aorta in strepozotocin-induced diabetic and spontaneously hypertensive rats. Methods The animal model of diabetes with and without hypertension were made on SHR (SHRDM group) and SD (SDDM group) rats respectively by injection of streptozotocin. The opening angle (OA) of their abdominal aorta (AA) was studied by microscope and compare image analysis system.Results (1) OA of AA in SD group became bigger from 1st week to 4th week, and then turned smaller, after 8th weeks became stable. (2) OA in SDDM group increased rapidly from 1st week to 4th week, decreased greatly within 4th to 8th weeks, and increased rapidly again after 16th weeks. OA in SDDM group was smaller at 8th or 16th week (P<0.05) and bigger at 4th or 24th week (P<0.01) than that in SD group. (3) The tendency of OA in SHR group turned out contrary to that in SDDM group , which was bigger than that in SD group at 1st, 8th, 16th week (P<0.01) and smaller at 4th weeks (P<0.01). (4) The change of OA in SHRDM group was similar to that in SDDM group, but smaller at 4th week ( P<0.01 ) and bigger at 8th or 16th week (P<0.05) than SDDM group. Conclusions The zero-stress state of abdominal aorta was abnormal in diabetic and hypertensive rats. The contrary tendency of OA between diabetic and hypertensive groups at early stage suggests that there exsits un-uniform growth obviously in big artery wall of diabetes and hypertension, but the patterns are different.