Movement Effect And Mechanism Of The Spontaneously Hypertensive Rat Anp And Npr-amrna Expression

Objective: This research is intended to explore the preventive effects against hypertension and its complications aroused by appropriate exercise and its mechanism, and to provide theory evidences for the prevention against hypertension and its complications by investigating the influences exercise has on the ANP amount of plasma and myocar of spontaneous hypertension rats, and the NPR-AmRNA expression of myocar and kidney.Methods: 16 Wistar male rats were divided randomly into control group(Group WC)and training(Group WT).16 SHR male rats were divided randomly into control group (Group SC)and training(Group ST), with 8 in each. Group WT and Group ST do 60 minutes swimming without loading everyday for 6 days per week during the continuous 8 weeks. During the test period, the blood pressure and weight of big rats were tested every week.8 weeks later, we respectively measured heart index of rats, the ANP amount of plasma and myocar, the NPR-AmRNA expression of myocar and kidney, the AngⅡamount of plasma and myocar, and the cGMP amount of myocar and kidney in every single group.Results:1.8 weeks of experiments later, the blood pressure in SHR control group obviously ascended compared with that before the test (P<0.01); the blood pressure in SHR training group ascended as well, but no conspicuous difference from that before the test(P>0.05); the blood pressure in SHR training group obviously descended more than that in SHR control group (P<0.01). All of those outcomes indicated that training could slow down the increase of blood pressure of rats in SHR training group. The weight in Wistar training group was obviously lower than that in Wistar control group(P<0.01), and the weights in SHR training group was obviously lower than that in SHR control group(P<0.01). Those proved the effects training had has on reducing the weights of Wistar rats and SHR rats.2. 8 weeks of experiments later, the heart coefficient in SHR control group was saliently higher than that in Wistar control group(P<0.01)and that in Wistar training group(P<0.05),which indicated hypertension was attributed to the increase of the heart coefficient. The fact that the heart coefficient of Wistar training group was saliently higher than that in Wistar control group(P<0.05)illustrated training played a role of raising the heart coefficient of normal rats. The outcome that the heart coefficient in SHR training group was saliently lower than that in SHR control group(P<0.05)showed training could descend the heart coefficient of hypertensive rats.3. 8 weeks of experiments later, the ANP amount of plasma in SHR control group and SHR training group conspicuously rose compared with that in Wistar control group(P<0.01), which indicated hypertension was attributed to the increase of the ANP amount of plasma . Training could not significantly increase the ANP amount of plasma of hypertensive rats was identified by the fact that the ANP amount of plasma in SHR training group increased compared with that in SHR control group, but not obvious(P>0.05).The AngⅡamount in SHR control group and SHR training group saliently rose compared with that in Wistar control group(P<0.01), which indicated salient increase of AngⅡamount of plasma of hypertensive rats. The AngⅡamount of plasma in Wistar training group rose compared with that in Wistar control group , but no conspicuous difference(P>0.05), and the AngⅡamount in SHR training group declined compared with that in SHR control group, with no obvious difference, either(P>0.05), both of which showed us training had no significant effects on the AngⅡamount of normal and hypertensive rats.4. 8 weeks of experiments later, the ANP amount of myocar in Wistar training group conspicuously acsended compared with that in Wistar control group(P<0.01), which indicated training worked on raising the ANP amount of myocar of normal rats. The ANP amount of myocar in SHR training group rose compared with SHR control group, but no big difference(P>0.05). The fact that the AngⅡamount of myocar in SHR control group and SHR training group saliently rose compared with that in Wistar control group(P<0.01)proved the AngⅡamount of myocar in hypertensive rats was conspicuously higher than that in normal rats. Compared with SHR control group, AngⅡamount of myocar in SHR training group conspicuously declined(P<0.01), which indicated training could reduce the AngⅡamount of myocar in hypertensive rats.5. 8 weeks of experiments later, NPR-AmRNA expression of myocar in Wistar training group saliently rose compared with Wistar control group(P<0.05), and so was NPR-AmRNA expression of myocar in SHR training group compared with SHR control group(P<0.01), which indicated training played a role in increasing the NPR-AmRNA expression of myocar of normal and hypertensive rats. The outcome that the NPR-AmRNA expression of kidney in SHR training group conspicuously rose compared with that in SHR control group(P<0.05) indicated training played a role in increasing the NPR-AmRNA expression of kidney of hypertensive rats.Conclusion:1. Long-term appropriate and regular exercise can significantly inhibit the further increase of SHR blood pressure, and can mitigate the hypertension. Meanwhile in works on inhibiting the weight of Wistar and SHR rats from increasing.2. The experiment results indicate ANP and NPR-A play an important role in training's preventing hypertension and protecting heart from injuring. It might works like this: long-term appropriate and regular exercise can increase the ANP amount of plasma of SHR and their activity. Meanwhile training raises the expression of NPR-AmRNA (the receptor of ANP ) and enhances the cGMP amount in the myocar and kidney of the hypertensive rats through which ANP could play against myocardial hypertrophy and proliferation and ANPⅡcould inhibit blood pressure raising and myocar hypertrophy.