糖尿病与高血压糖尿病大鼠心脏β-AR变化的比较  

Changes of Cardiac β-adrenoceptor and Cardiac Function in between Diabetic and Hypertensive-diabetic Rats

作　　者：宫海滨[1] 张清林[1] 王雷[1] 王洁[1] 王秀力[1] 

机构地区：[1]江苏省徐州市中心医院心内科,徐州市心血管病研究所,221009

出　　处：《中华全科医学》2008年第11期1103-1104,共2页Chinese Journal of General Practice

基　　金：国家自然科学基金资助项目(30572073);江苏省自然科学基金项目(DK2005428);江苏省卫生厅重大项目(K200402);江苏省"六大人才高峰"第三批资助项目(C类)

摘　　要：目的比较糖尿病与高血压糖尿病大鼠心脏β肾上腺素受体(β-AR)及其介导的功能变化。方法采用链脲佐菌素(STZ)注射制胰岛素依赖性糖尿病大鼠模型和高血压糖尿病大鼠模型,放射配体结合实验和离体左心房收缩功能实验等方法观察心脏β-AR及功能的改变。结果与对照大鼠相比,糖尿病大鼠心脏β-AR的最大结合容量(Bmax)下降31%(P<0.05),KD值不变;高血压糖尿病大鼠心脏β-AR的Bmax增加27%(P<0.05)。与对照大鼠相比,糖尿病大鼠左心房β-AR介导的最大收缩反应(Rmax)下降69%(P<0.01);高血压糖尿病大鼠左心房β-AR介导的Rmax下降40%(P<0.05),pD2值不变。结论糖尿病时,大鼠心脏β-AR数量减少,其介导的Rmax也是降低的;而高血压糖尿病时,虽然大鼠心脏β-AR数量代偿性增加,但其介导的Rmax是降低的,其可能与β-AR后信号转导效应减弱有关。Objective To study the changes of cardiac β-adrenoceptor（β-AR） and cardiac function in diabetic and hypertensive-diabetic rats. Methods The models of diabetic and hypertensive-diabetic rats were induced by streptozotocin （ STZ）, and all the works were studied by radioligand binding assays and functional determination of isolated left atria. Results Compared with control, the β-AR density was decreased 31% （ P 〈 0.01 ） and the KD value was not changed in diabetic rats, then the β-AR density was increased 27% （P 〈 0.01 ） in hypertensive-diabetic rats. In diabetic rats and hypertensive-diabetic rats, the maximal positive inotropic response （Rmax） induced by isoproterenol in left atria of rat was decreased 69% （P 〈 0.01 ） and 40%, respectively. The pD2 value was not altered in both groups. Conclusions The results suggested that the both of cardiac β-adrenoceptor density and cardiac function were decreased in diabetic rat. The cardiac β-adrenoceptor numbers was compensative increasing in hypertensive-diabetic rat, but the Rmax of left atria was decreased, which may be associated with the reduction of post-receptor signal transduction.

关 键 词：糖尿病 高血压 Β肾上腺素能 心脏 

分 类 号：R587.1[医药卫生—内分泌] R54[医药卫生—内科学]