牛初乳短链IGF-1治疗对链脲佐菌素糖尿病大鼠心肌血管紧张素Ⅱ含量的影响

Effects of Bovine Colostrum Truncated Insulin like Growth Factor 1 on Cardiac Content of Angiotension Ⅱ in Streptozocin induced Diabetic Rats

目的 观察牛初乳短链IGF 1 (BC tIGF 1 )对STZ糖尿病大鼠心肌血管紧张素Ⅱ (ATⅡ )含量的影响。方法 链脲佐菌素 (STZ) 5 5mg/kg腹腔注射 (IP)建立糖尿病大鼠模型 ,分DM C组 (NS 0 .1ml/dIP)、DM BC(BC tIGF 1 2 5 0ng·kg-1·d-1IP)。正常对照组 (NC)未予特殊处理 ,每组n =5。 6周后实验结束时测定各组大鼠体重、心重、快速血糖、FMN、血清GH、IGF 1和心肌IGF 1、ATⅡ。结果 (1 )DM BC的血糖、FMN明显低于DM C ,但仍高于NC。 (2 )DM C血清GH、心肌ATⅡ含量较NC分别升高 6 6 .1 %、1 .44倍 (P <0 .0 1 ) ;DM C组的血清IGF 1、心肌IGF 1含量较NC降低 6 3.2 % (P <0 .0 1 )、5 5 .3% (P <0 .0 5 ) ;与DM C相比 ,DM BC血清GH明显降低 (P <0 .0 1 ) ,心肌IGF 1含量升高 99.6 % (P <0 .0 5 )、心肌ATⅡ明显降低 (P <0 .0 1 )。结论 STZ糖尿病大鼠心肌局部存在RAS激活 ;BC tIGF

Purpose To investigate the effect of Bovine Colostrum truncated insulin like growth factor 1(BC tIGF?1) on cardiac content of angiotension Ⅱ(ATⅡ) in Streptozocin induced (STZ induced) diabetic rats. Methods Diabetes was induced in male SD rats (180～200 g) by intraperitoneal injection (IP) of STZ at a dose of 55 mg/kg and animals were divided into two groups:DM?C group ( n =5),treated with NS 0.1 ml/d,IP; DM?BC ,treated with BC tIGF?1 250 ng·kg -1 ·d -1 IP.Therapy lasted for 6 weeks.The blood glucose was measured at the beginning and end of therapy.The plasma FMN,GH,IGF?1 and cardiac tissue level of IGF? 1 and ATⅡ were determined radioimmunologically. Results DM?BC has a lower level of BG,FMN than DM?C.Compared with NC,the cardiac content of ATⅡ in DM?C increased by 66.1% ( P <0.01).The plasma GH of DM?C was 1.44 times higher than that of normal group ( P <0.01).The plasma IGF?1 and the cardiac content of IGF?1 of DM?C were significantly lower than those in NC ( P < 0.05 );Compared with DM?C group,the cardiac content of IGF?1 in DM?BC markedly increased ( P < 0.05 ) while the cardiac content of ATⅡ significantly decreased ( P <0.01). Conclusions STZ induced diabetic rats had a hypersecretion of ATⅡ.Treatment with BC tIGF?1 decreased cardiac content of ATⅡ in STZ diabetic rats while improved the metabolic control.