去肾交感神经术对心梗犬下丘脑Ang（1-7）及酪氨酸羟化酶的影响

摘要

O bjective: To explore the effect of renal denervation(RDN)on hypothalamus angiotensin(1-7)[Ang(1-7)] and tyrosine hydroxylase(TH)in myocardial infarction (MI) dogs. Methods: Eighteen healthy mongrel dogs were randomly divided into control group, model group and RDN group. Myocardial infarction model was made in model group and RDN group by gelatin sponge embolization of the left anterior descending artery. One week after MI, RDN was given to dogs in RDN group. Echocardiography examination was administered four weeks after MI. Levels of hypothalamus angiotensin (1-7), expression of TH protein, expression of ACE2 and MasR mRNA in each group were detected respectively. Results:Compared with control group, heart function was reduced in model group, levels of hypothalamus Ang (1-7), TH protein, ACE2 and MasR mRNA were higher in model group and RDN group (P<0.01). Heart function was improved in RDN group;relatively expression of TH protein was decreased (P<0.01);levels of Ang (1-7)and expression of ACE2, MasR mRNA were remarkablely increased in hypothalamus in RDN group , as compared to the model group (P<0.01). Conclusion:RDN is able to increase the levels of hypothalamus ACE2 and Ang(1-7), inhibit the activity of adrenergic neuron, and improve heart function in MI canine model.%目的：研究去肾交感神经术（RDN）对心肌梗死（MI）犬下丘脑血管紧张素（1-7）[ Ang（1－7）]及酪氨酸羟化酶（TH）的影响。方法：健康杂种犬随机分为对照组、模型组、去肾交感神经术治疗组（RDN组），每组6只。对模型组、RDN组行前降支明胶海绵栓塞构建MI模型，对照组只行冠脉造影检查。建模后1周，RDN组行去肾交感神经术，余两组只行肾动脉造影检查。建模后4周行超声心动图检查，分别检测下丘脑Ang（1－7）含量，TH蛋白表达及ACE2、MasR mRNA表达。结果：模型组心功能降低，下丘脑Ang（1－7）含量、TH蛋白表达水平升高，ACE2、MasR mRNA表达增加；行RDN后，心功能较前改善，下丘脑TH蛋白表达水平明显降低，Ang（1－7）水平进一步升高，ACE2、MasR mRNA表达进一步增加，差异均具有显著统计学意义（P＜0．01）。结论：去肾交感神经术可以增加MI犬下丘脑ACE2表达，促进Ang（1－7）生成，降低肾上腺素能神经元活性，改善MI后心功能。