Effect of active immunization with peptides corresponding to the second extracellular loop of alpha1-adrenoceptor on vascular function in rats
会议名称：《中国生理学会第23届全国会员代表大会暨生理学学术大会》
会议日期：2010年
学科分类：1002[医学-临床医学] 100201[医学-内科学(含：心血管病、血液病、呼吸系病、消化系病、内分泌与代谢病、肾病、风湿病、传染病)] 10[医学]
基 金：supported by the 973 Program(No.2006CB503806) and China Postdoctoral Science Foundation
关 键 词：receptor,adrenergic,alpha1 autoantibody vascular dysfunction hypertension
摘 要：Backgroud:Autoantibody against the second extracellular loop ofα-adrenoceptor(α-AA) which had been found in hypertensive patients possess agonist-like activity as phenylephrine evidenced by previous studies, however,long-term stimulation ofα-AA did not modify the mean arterial pressure in spite of the occurrence of cardiac and vascular remodeling,and the mechanism was not fully ***:In this study,the effect of acuteα-AA administration on mean arterial blood pressure was observed;the models with antibodies against theα-adrenoceptor were established by immunizing Wistar rats with the synthesized peptide corresponding to the second extracellular loop ofα-adrenoceptor(α-AR-EC).The age-matched male Wistar rats received a mixture of saline and immunological adjuvant as sham immunized *** the rats were raised for 8 *** blood pressure and heart rate were measured every *** reactivity experiments were performed in segments of thoracic ***-1(ET-1) concentration and iNOS expression were determined by ELISA and immunochemistry ***:The mean arterial pressure significantly increased after the administration ofα- AA in *** the systolic blood pressure of immunized rats having no difference with sham group,the isolated thoracic arteries showed hyperresponsiveness to phenylephrine and decreased endothelium-dependent relaxation at 6 and 8 months after initial ***,the plasma endothelin-1(ET-1) concentration and iNOS expression in vascular endothelium from the thoracic aorta increased,indicating that the long-term stimulation might contribute to endothelium injury,which plays an important role in the vasomotor dysfunction and enhanced pressor ***:The results demonstrated thatα-AA could contribute to vasomotor dysfunction in rats by vascular endothelial damage and increase iNOS expression,and might play a particular role in the pathological changes of hypertension.