Remodeling Of Sympathetic Nerve In Atherosclerosis And The Protective Effects Of Atorvastatin

Objective Raise atherosclerosis model and observe the local density of sympathetic nerves in heart tissue:the expression of tyrosine hydroxylase(TH),growth associated protein 43(GAP43),neuro growth factor(NGF),which is may be the relative moleculer,and observe the protective effect of atorvastatin and the possible mechanisms.Methods Twenty-two male New Zealand white rabbits were divided into three groups randomly:control group(C组,n=6组);atherosclerosis group(AS组,n=8);atorvastatin group(ATV组,n-8).After 8 weeks,take suction rabbit central artery empty stomach blood preparation and determin the level of total cholesterol(TC),low density lipoprotein(LDL), using BackmaanLX20 automatic biochemistry analyzer.RT-PCR and immunohistochemisrey are used to determine the level of TH and GAP43,NGF respectively。Results TH,GAP43,NGF are widely expressed in left ventricle mussles.the TC level of the three groups at the eighth week:The TC level in AS group is increased significantly compared to C group(P＜0.01),The TC level in ATV group is decreased significantly compared to AS group(P＜0.01),while there is no significant differences in ATV group compared to C group(P＞0.05).The LDL level in AS group is increased significantly compared to C group (P＜0.01),The LDL level in ATV group is increased significantly compared to AS group (P＜0.01),while there is no significant differences in ATV group compared to C group(P＞0.05). At the eighth week,the weight of the rabbits in all groups are increased significantly compared to pre-experiment,but there is no significant differences among groups(P＞0.05).The expression of GAP₄₃in AS group is increased significantly compared to C group(0.408±0.060 vs 6.280±0.792,P=0.002),The GAP₄₃level in ATV group is decreased significantly compared to AS group(2.641±0.626 vs 6.280±0.792,P= 0.009),while there is significant differences in ATV group compared to C group(2.641±0.626 vs 0.408±0.060,P= 0.032).The expression of NGF in AS group is increased significantly compared to C group(5.663±0.306 vs 1.116±0.234,P＜0.001),The NGF level in ATV group is decreased significantly compared to AS group (3.397±0.193 vs 5.663±0.306,P=0.003),while there is significant differences in ATV group compared to C group(3.397±0.193 vs1.116±0.234,P=0.003).the result of GAP₄₃and NGF with Immunofluorescence method:the fluorescence of GAP₄₃and NGF in cardiac muscle fibers and interstitial in C group is feeble,the Immunofluorescence of GAP₄₃and NGF in AS group is much more reinforced than C group,the fluorescence of GAP₄₃and NGF in ATV group is decreased significantly compared to AS group,while is still increased than C group,the expression of TH with RT-PCR:the relative amount of the objective gene TH in AS group is increased significantly compared to C group(0.64±0.057457230vs0.0003902±0.00010388,P＜0.001),the relative amount of THmRNA in ATV group is decreased significantly compared to AS group(0.1197±0.022303463 vs 0.64±0.057457230,P=0.003), while is still higher compared to C group(0.1197±0.022303463 vs 0.0003902±0.00010388,P =0.049).Conclusion The oxidative stress in heart tisssue is the reason that causes the impairment of cardiac local sympathetic nerves and over-expression of NGF;the latter causes the regeneration and over- regeneration of sympathetic nerves after impairment:the TH and GAP₄₃ is over expressed;Atorvastatin can alleviate this oxidative stress on heart tissue.The three above index are all decreased significantly compared to AS group.It can alleviate the remodelling of sympathetic nerves in cardiac tissues.