ABSTRACT
BACKGROUND:No uniform standard for constructing the animal model of exercise-induced myocardial ischemia injury results in the incomparability among research results and impedes the development of sport medicine especial y in the cardiovascular field;thereby, it is imperative to reach an agreement in constructing criteria. OBJECTIVE:To explore the method of establishing the rat model of myocardial ischemia induced by running. METHODS:Total y 96 female Sprague-Dawley rats were randomly divided into rest control group, isoprenaline group and 10 exercise groups (1-and 3-time moderate-intensity exercise groups, 1-, 2-and 3-week moderate-intensity exercise groups, 1-and 3-time high-intensity exercise groups, 1-, 2-and 3-week high-intensity exercise groups). After exhaustive exercise, myocardium was col ected for morphological observation by hematoxylin-eosin staining, serum levels of myocardial enzymes and cardiac troponin I were detected, and the expressions of Bcl-2 and Bax were detected by real-time PCR. RESULTS AND CONCLUSION:(1) Hematoxylin-eosin staining showed that the damage degree was more severe with the time of exercise, and the high-intensity exercise groups were more severe than those in the moderate-intensity exercise groups. (2) The activity of serum glutamic-oxaloacetic transaminase and lactic dehydrogenase was significantly increased after 1-week moderate-intensity exhaustive exercise (P<0.05 or P<0.01). From the beginning of the 3-time high-intensity exhaustive exercise, the activity of glutamic-oxaloacetic transaminase and lactic dehydrogenase was significantly increased (P<0.05 or P<0.01). (3) Cardiac troponin I content change trend was basical y the same as glutamic-oxaloacetic transaminase and lactic dehydrogenase changes, but cardiac troponin I content in the moderate-intensity exhaustive exercise groups was significantly higher than that in the rest control group until 2 weeks. The Bcl-2/Bax ratios in al exercise groups were significantly lower than that in the rest control group (P<0.05 or P<0.01);those in the 1-and 3-time high-intensity exercise groups were significantly higher than in the isoprenaline group (P<0.05 or P<0.01);and those in moderate-intensity groups were higher than in the isoprenaline group (P<0.05 or P<0.01). (4) In conclusion, 2-week high-intensity and 3-week moderate-intensity exhaustive exercise can induce myocardial ischemia injury, and pathological analysis, serum levels of myocardial enzymes and cardiac troponin I can be used as the evaluation indexes, while apoptosis regulation genes just as the reference index.
ABSTRACT
@#Objective To explore the effects of estrogen,sport walking with weight and estrogen plus sport walk on serum lipid,bone metabolism and bone mineral density(BMD) in postmenopausal women.Methods 52 postmenopausal women were divided into the hormone replacement therapy(HRT) group(n=12),sport walking with weight group(Sp group,n=14),HRT + Sp group(n=12) and control group(n=14).HRT group took compound nylestriol,Sp group took sport walking with 5 kg weight and exercise intensity was from 60% to 80% VO2max,HRT+Sp group received two treatments as HRT group and Sp group.The experimental duration consisted of six months.Results The total cholesterol(TC),TC/high density lipoprotein cholesterol(HDL-C),alkaline phosphatase(APL) and urine calcium(Ca)/creatinine(Cr) were markedly lower in three experimental groups than the control group and before experiment(P<0.05 or P<0.01),HDL-C in Sp and HRT+Sp groups were markedly higher than the control group and before experiment(P<0.05),BMD of spine(L2～L4) and left trochanter in three experimental groups were markedly higher than the control group(P<0.01) and before experiment(P<0.0).Conclusion Both estrogen replacement therapy and sport walking with weight effectively improve serum lipid,prevent and reverse osteoporosis induced by menopause in women.