降钙素基因相关肽对不同程度冠脉狭窄时的心脏功能的影响

本实验观察了冠脉内注射降钙素基因相关肽（ＣＧＲＰ０．３μｇ／ｋｇ）对正常及不同程度冠脉狭窄犬的心功能的影响。结果表明正常犬冠脉内注射ＣＧＲＰ后，平均动脉压（ＭＡＰ）下降１．２ｋＰａ（Ｐ＜０．０５），同时，心率（ＨＲ）、心输出量（ＣＯ）、左室收缩压峰值（ＬＶＳＰ）均不同程度增加；左室舒张末压（ＬＶＥＤＰ）轻度降低。在中度狭窄３０ｍｉｎ后，冠脉内注射ＣＧＲＰ对ＨＲ、ＭＡＰ无明显影响；而重度狭窄后注射ＣＧＲＰ，ＭＡＰ由狭窄时降低逐渐增高，ＨＲ由增快而变慢。ＣＯ、ＬＶＳＰ均显著增高，ＬＶＥＤＰ降低，此作用较冠脉狭窄前更为明显。提示ＣＧＲＰ扩张冠脉动脉，增加冠脉血流量和心排血量，增强心肌收缩力，对缺血心脏功能有保护作用。

EFFECTS OF CALCITONIN GENE RELATED PEPTIDE ON CARDIAC FUNCTION IN CORONARY STENOSIS OF DIFFERENT GRADES

Effects of intracoronary injection of calcitonin gene related peptide (CGRP) on cardiac function of normal dogs and dogs with coronary stenosis of different grades were observed. The results showcd that mean arterial pressure (MAP) and left ventricular end diastolic pressure (LVEDP) decreased ( P <0.05), while heart rate (HR) cardiac output (CO) and left ventricular systolic pressure (LVSP) increased to different extent after injection of CGRP in normal dogs. No significant influence on MAP and HR was observed,when CGRP was given intracoronarily 30min following moderate coronary stenosis. In dogs received intracoronary injection of CGRP 30min after severe coronary stenosis, MAP elevated HR decreased gradually, CO, LVSP increased and LVEDP decreased.These results suggest that CGRP may have protective effect on ischemic myocardial function by increasing coronary blood flow and strengthening myocardial contractility.