耐力运动和力竭运动对大鼠心脏降钙素基因相关肽及其受体样受体表达的影响

Effects of Endurance Exercise and Exhausted Exercise on Calcitonin Gene-Related Peptide and Calcitonin Gene-Related Peptide Receptor in the Heart of Rats

目的:探讨耐力运动和力竭运动对降钙素基因相关肽(CGRP)及其受体样受体(CRLR)在大鼠心脏组织中表达的影响及其作用机制。方法:健康雄性SD大鼠60只,随机分为对照组、耐力运动组和力竭运动组。耐力运动组和力竭运动组进行10周的跑台耐力训练,力竭运动组在最后一次训练后48h进行连续3天的力竭运动。采用放射免疫法、免疫组化SABC法、免疫荧光法和计算机图像分析技术检测心肌组织CGRP含量和CRLR表达。结果:耐力运动组心肌组织CGRP含量和CRLR表达明显高于对照组(P<0.05);力竭运动组心肌组织CGRP含量和CRLR表达明显低于耐力运动组(P<0.05)。结论:长期耐力运动使心脏CGRP含量增加,CRLR表达上调,增强了CGRP对心脏的作用;力竭运动导致心脏CGRP含量下降,CRLR表达下调,使CGRP对心脏的保护作用减弱。

Objective The effects of endurance exercise and exhausted exercise on the expression of calcitonin gene-related peptide （CGRP）and calcitonin receptor-like receptor （CRLR）in the heart of rats were studied. Methods Sixty healthy male SD rats were randomly divided into control group,endurance exercise group and ex- hausted exercise group. Endurance exercise group and exhausted exercise group underwent 10-week treadmill training. 48 hours after the last training,exhausted exercise group underwent consecutive 3-day exhausted exercise. The content of CGRP and the expression of CRLR in myocardium were investigated using radioimmunoas- say,immunohistochemistry,immunofluorescence and the technique of computer image analysis. Results As compared with the control group, the content of CGRP and the expression of CRLR were significant higher in endurance exercise group（P〈0.05）. The content of CGRP and the expression of CRLR in exhausted exercise group were significant lower than that in endurance exercise group （P〈0.05）. Conclusion The results suggested that the synthesis and secretion of CGRP increased and the expression of CRLR upregulated by endurance exercise, which may enhance the effect of CGRP on the heart. After exhausted exercise,CGRP was largely consumed and the expression of CRLR downregulated,which may attenuate the protection of CGRP on heart.