The Role Of Skeletal Muscle In The Long-term Aerobic Exercise Affects The Blood Pressure Of Pressure Overload Mice

Objective:It has been shown that the appropriate exercise can effectively reduce the blood pressure of patients with hypertension,and the physiological structure and function of skeletal muscle adaptation and related research but drop mechanism of blood pressure in skeletal muscle in motion has not been reported,this study mainly uses the coarctation of the aorta(transverse aortic,constriction,TAC)of pressure overload hypertension in mice the model of successful modeling,hypertensive mice were subjected to long-term aerobic exercise intervention.Through the observation of long-term aerobic exercise on blood pressure in mice skeletal muscle physiological structure and vascular regulation factor(vascular e The effect of VEGF growth factor(ndothelial)expression,to explore the possible role of skeletal muscle in the mechanism of exercise induced hypotension,so as to provide experimental basis for the exercise therapy of hypertensionResearch method:8 week old wild type BALB/C 60 male mice were randomly divided into control group(CON),operation group(TAC),exercise group(TAE)surgery group 3.Surgery group and exercise group were grouped at the same time ascending aortic coarctation operation,hypertension model.Three normal feeding group,surgical operative recovery exercise group were 4 days,treadmill exercise treadmill,the slope is 0o.with incremental exercise load,exercise time,12m/min and30 min increased to 15m/min,60 min,fifth weeks by 15m/min,60 min,each Week 5days,the rest of the weekend,a total of ten weeks.After the experiment using Millar catheter in three groups of mice was measured in the right carotid artery pressure;after the gastrocnemius muscle were removed on both sides of the white part of the fascia,the gastrocnemius muscle weighing and recording;portion of the gastrocnemius muscle of 10% formalin fixed,gastrocnemius muscle fiber cross-section calculation the area of staining by conventional HE;the number of microvessels were stained with vascular CD31 immunohistochemical detection statistics of gastrocnemius muscle gastrocnemius;RT-PCR method is applied to the rest of the detection of vascular endothelial growth factor(VEGF)expression in M RNA by Western Blot method was used to detect the expression of VEGF protein.Result:In the aerobic process,three groups of mice with hair smooth and moist,no depilation,lively,responsive,eating and drinking water regularly,normal growthand development,the weight of 3 groups of mice were increased steadily.The aortic manometry showed the blood pressure in TAC group(160±7.2mmHg)was significantly higher than that in normal CON group(100±4.6mmHg),the difference was significant(P<0.01);group TAE(125±5.3mmHg)of the blood pressure lower than the TAC group,significant difference(P<0.01).Mice gastrocnemius muscle weighing results,TAC group of gastrocnemius muscle weight was significantly lower than that of C ON group(P<0.01),TAE group of gastrocnemius muscle weight is higher than that of TAC group(P<0.05);HE staining showed that compared with group CON,the cross-sectional area of skeletal muscle in TAC group were significantly decreased(P<0.01),TAE group in skeletal muscle cross-sectional area than in the TAC group increased(P<0.05)immunohistochemical results show that compared with the CON group,the number of TAC group of skeletal muscle vascular decreased significantly(P<0.01),the number of blood vessels in TAE group than in the TAC group increased(P<0.05).Compared with CON group,VEGF M group the expression of TAC mice without RNA Significant difference(P>0.05),the VEGF mRNA expression in group TAE was significantly higher than that in group TAC(P<0.01);compared with CON group,the expression of VEGF in the TAC group was reduced(P<0.01)in the P<0.05 group,and the expression of TAC in the TAE group was higher than that in the control group.Conclusion:(1)The pressure overload model established in this experiment is reasonable with the aerobic exercise intervention model(2)Exercise can reduce blood pressure in hypertensive group(3)Exercise can promote the expression of VEGF in gastrocnemius muscle in mRNA and protein level,but also can promote the increase of gastrocnemius capillary number.Exercise can also promote skeletal muscle weight and cross-sectional area increases.(4)In the process of movement of lowering blood pressure,increased expression of VEGF in skeletal muscle in mRNA and protein level,resulting in the number of capillaries in skeletal muscle increased,causing blood peripheral resistance decreased;while skeletal muscle hypertrophy makes cardiac afterload reduction,which is an important role in skeletal muscle in the buck.