Exercise On Myocardial And Vascular Smooth Muscle In Shr Ho-1mrna Study On The Expression And Effect Of Ho Activity And Its Mechanism

Objective: Observe training effects on HO activity and expression of HO-1 protein inthe aorta or cardiac muscle of spontaneously hypertensive rats (SHR).inquiry into thefeasible aerobic sports prevent from the development of hypertensive and cardiachypertrophy as well as its mechanisms, thus exercise provides the new academic basesfor the prevention and cure of the hypertension and the cardiac hypertrophy occurrenceand development.Methed: The male SHR are randomly divided into the SHR group (S) and training SHRgroup (T); The male Wistar rats are the normal matched control group (C). S groupcarries on 60 minutes swimming 6 time a week, all rats feed normal feedstuff for 9weeks. The HO activity and expression of HO-1 protein in the aorta and cardiacmuscle,hearts index and content of plasma CO are used to observe and evaluate.Result: adopt 11.0 software packages of SPSS to these results:1. After 9-week swimming exercise, the resting blood pressure was increased by1.7%(P＞0.05) in exercise group while it was significantly increased by 10.3% (P＜0.01)in SHR group compared with that of pre-experiment.2. Compared with C, S group Heart Index and expression of BNP protein go upobviously (P＜0.01); Compared with S, T group Heart Index and expression of BNPprotein obviously descended(P＜0.01).3. Compared with C, S group expression of HO-1 protein in the aorta and cardiacmuscle go up obviously (P＜0.01), S group HO in the aorta and cardiac muscle as wellas content of plasma CO obviously descended(P＜0.05, P＜0.01). Compared with S, Tgroup HO activity in the aorta and cardiac muscle as well as content of plasma CO goup obviously(P＜0.05, P＜0.01).Conclusion: the long-term regular moderate exercise training can inhibit the increase ofblood pressure in hypertension. One of the mechanisms of training induced preventingand curing hypertension and cardiac hypertrophy may be mediated by up-regulating theactivity of HO/CO system and expression of HO-1 protein, which suggests that HO isone of the vasoactive peptides that take part in regulating blood pressure and thedevelopment of cardiac hypertrophy through moderate exercise, which possiblemechanism is :Among the key metabolic pathways that physiologically yield CO is the HO catalyzed degradation of heme. CO induced relaxation of VSMCs by severalpathways comprising the stimulation of sGC, yield cGMP, opening of calcium-activatedK~+ channel, or inhibition of cytochrome P450-dependent mono-oxygenase. The HO/COmetabolic pathway is believed to be involved in the regulation of basal tone ofresistance blood vessels, growth of VSMC, and vascular remodeling.2. the feat exercise can descend obviously Heart Index and expression of BNP protein, itshows that the long-term regular moderate exercise lower or prevent from thedevelopment of cardiac hypertrophy which caused by the hypertension.