Effects of Acute Exhausted Exercise on the Myocardial HSP70 and Plasma ANP of Rats in a High Temperature Environment
- VernacularTitle:高温环境下急性力竭运动对大鼠心肌HSP70及血浆心钠素的影响
- Author:
Aiping LI
;
Shuqiang CUI
;
Jincheng XU
;
Qi GAO
;
Jiexiu ZHAO
- Publication Type:Journal Article
- Keywords:
heat exposure;
exercise;
HSP70;
ANP
- From:
Chinese Journal of Sports Medicine
2010;(2):188-191
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect of acute exhausted exercise in high temperature environment on the expression of myocardial HSP70 and plasma ANP level of in rats. Methods Forty eight male Sprague-Dawley rats was randomly and equally assigned to the following six groups:control group(C),exercise group(E),one-hour heat exposure group (H), heat exposure and exercise group (HE), exercise and 24 hours after exercise group(E'),heat exposure and 24 hours after exercise(HE'). Each group consisted of 8 rats. Rats in E,HE,E' and HE' ran on a treadmill until exhaustion, while rats in H and H' were exposed in a high temperature environment (33℃ ,50%RH) for one hour. Rats in C,E,HE and H were killed immediately after exercise or heat exposure. Rats in HE' and E' were killed 24 hours after exercise. Samples from myocardium and serum were collected for determining HSP70,ANP and CK-MB. Results(1) HSP70 levels in groups E and E' are significantly higher than that in group C(P<0.05 and P<0.01,respectively),and the level in group HE' is significantly higher than that in groups H and E'(P<0.01 );The HSP70 level in group H is significantly higher than that in group C. (2) The ANP and CK-MB levels in group E are Significantly higher than that in group C.and in group HE is higher than in group H (P<0.05);The HSP70 levels in group E' and HE' significantly decrease comparing to that in groups E and HE (P<0.01). Conclusions(1)Both heat exposure and exercise can induce the increased expression of myocardial HSP70 in rats and the peak expression is seen 24 hours after exercise. The increased expression of HSP70 may have protective effects on the heat-induced myocardial injury. (2) The increased ANP levels in plasma immediately after exhausted exercise improves the blood circulation in myocardium and hints the potential possibility of myocardial damage. However,the high temperature environment does not strengthen the increase of plasma ANP level that caused by exhaustive exercise.
