| Atherosclerosis is a multi-pathogenies cardiovascular disease that severely impacts on human health. With the understanding of NO deeply,we find that the impairment of its bioactivity is closely related to the onset or progression of the AS process.More and more studies demonstrate that this substance has a wide range of biological properties'including modulation of vascular dilator tone,stimulation of antioxidant response, regulation of local cell growth,and protection of the vessel from injurious consequences of platelets and cells circulating in blood and is regarded as an anti-atherosclerotic factors.Regular exercise has been proved to have positive effect on AS,the mechanisms of reduction atherogenic risk of exercise are not completely understood.Recent reports show that exercise can improve synthesis and bioactivity of NO,which maybe a new mechanism of the effect of exercise on AS .This study observed the change of NOS expression,L-Arg/ADMA and the capacity of antioxide in apo-E deficient mice during the progression of AS after 10 weeks swimming. 1 Effect of Aerobic Exercise on Atheromatous Plaques Area and Lipid Levels inApoE-deficient MiceTo approach the effect and mechanism of aerobic exercise on formation of atherosclerotic lesions.METHODS:ApoE deficient mice randomly were divided into control group and exercise group(swimming,2h/d,5d/w,10 w),determine the lession area and serum lipid levels.RESULTS:The lession area in the aortic sinuses of exercise mice was significantly less than that of the control mice(p<0.05).But the TC and LDLof exercise mice .increased remarkably(p<0.05).This result indicates thataerobic exercise significantly decreased the development of atherosclerotic plaque in ApoE-deficient mice ,but the mechanism does not depend on lipid level.2 Effect of Aerobic Exercise on Activity of NO in ApoE-deficient MiceAerobic exercise has been proved to upregulate the level of NO,but the effects of exercise on NO activity remain unknown when AS.METHODS: ApoE deficient mice randomly were divided into control group and exercise group(swimming,2h/d,5d/w,10 w), determine serum NO2~/NO3~,vessel cGMP and liver SOD,MDA respectively. RESULTS:Serum NO27NO3~,vessel cGMP and liver SOD levels increased singficintly,the level of MDA decreased remarkably. These observations indicate that the improvement of NO level and bioactivity in exercise mice was related to enhancement of antioxidant capacity.3 Effect of Aerobic Exercise on NOS in ApoE-deficient MiceTo approach the effect of aerobic exercise on NOS gene expression and protein expressiorf in ApoE deficient mice artery.METHODS: ApoE deficient mice randomly were divided into control group and exercise group(swimming,2h/d,5d/w,10 w),by RT-PCR method determin mRNA expression of vessel cNOS,iNOS,by immunohistochemical method ,NOS distribution of splanchnic vessels was studied with antibodies specific for eNOS or iNOS while NOS staining intensity was analyzed by computer image system.RESULTS:mRNA expression of cNOS increased significantly in exercise mice.cNOS staining intensities in EC were increased in exercise mice and iNOS staining intensities in smooth muscle cell were increased in control mice.These results demonstrate that exercise regulates NOS on transcription level and affects protein expression of NOS.4 Effect of Aerobic Exercise on Serum L-Arg and ADMA in ApoE-deficient MiceL-Arg is the substrate of NOS.ADMA, an endogenous competitive inhibitor of nitric oxide synthase, is increased in AS and inhibits bioavailability of L-Arg.The study tested the hypothesis that aerobic exercise can increase the ratio.METHODS: ApoE deficient mice randomly were divided into control group and exercise group(swimming,2h/d,5d/w,10 w),by HPLC method,serum L-Arg/AD MA were determined,serum creatinine and the ultrastructures of kidney wereobserved.RESULTS:Serum ADMA level was significiently decreased in exercise group.The results demonstrate that exercise can increase L-Arg/ADMA ratio and the mechanism of downregulation of exercise on ADM...
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