Ghrelin注射对大鼠血压和心肌收缩功能的影响  

Effects of intravenous injection of ghrelin on blood pressure and cardiac contractility in rats

作　　者：曹钰琨[1] 俞世强[1] 裴建明[2] 赵玉峰[2] 郑奇军[1] 王伟光[1] 

机构地区：[1]第四军医大学西京医院心血管外科 [2]第四军医大学生理学教研室,陕西西安710032

出　　处：《心脏杂志》2010年第5期673-676,共4页Chinese Heart Journal

摘　　要：目的:探讨促生长激素释放多肽(ghrelin,GRL)对大鼠心血管功能的影响及其意义。方法:将40只成年雄性SD大鼠分为对照组和4个剂量的GRL组,静脉注射GRL后测量血流动力学指标。随后采用单细胞动态边缘检测系统测定细胞收缩功能的变化。结果:①GRL各组平均动脉血压(MABP)较对照组明显下降(P<0.05)。②GRL各组单个心肌细胞收缩功能指标最大收缩幅度(PTA)、最大缩短和复长速率(±dL/dtmax)较对照组明显降低(P<0.05)。结论:GRL可剂量依赖性地降低大鼠的MABP,降低心肌细胞的收缩功能。AIM： To investigate the effect of ghrelin on the cardiovascular system. METHODS： 40 male Sprague-Dawley （SD） rats were randomized into control group and four drug groups with five rats in each group. After the rats were anesthetized, a microeatheter was inserted into the left ventricle through the right carotid artery, and left ventricular developed pressure （LVDP） , maximal velocity of left ventric- ular pressure development and decline （ ＋ LV dP/dtmax and - LV dp/dtmax） and heart rate （HR） were recorded by a biological signal collecting system. Simultaneously, mean arterial blood pressure （MABP） was measured by right femoral artery intubation. The rats were given either ghrelin （ 1 × 10^-7 - 1 × 10 -4 g/kg） or saline and MABP and left ventricular indexes were observed for 30 min. Contractile function of the myocytes were detected. RESULTS： No obvious changes of MABP were observed in control group after injection of saline. Intravenous （i. v. ） injection of ghrelin decreased MABP in a dose-dependent manner by 11.4% , 15.8% and 27.1% , respectively, in 10-6 g/kg, 10-5 g/kg and 10-4 g/kg groups. No significant difference was observed in LVDP, ＋ dp/dt - dp/dtm,x and HR 30 rain after i. v. injection of ghrelin. The PTA ＋ dL/dtmax, were significancly decreased in the GRL groups compared with the control group. CONCLUSION： Ghrelin decreases MABP of rats and contractile function of ventricular myocytes in a dose-dependent manner.

关 键 词：促生长激素释放多肽 血压 心肌收缩 大鼠 

分 类 号：R443.5[医药卫生—诊断学]