Agonistic AT_1 Receptor Autoantibody Increases in Serum of Patients with Refractory Hypertension and Improves Ca^(2+) Mobilization in Cultured Rat Vascular Smooth Muscle Cells  

作　　者：Feng Zhu Yanxiang Sun Yuhua Liao Yumiao Wei Ming Chen Min Wang Zihua Zhou 

机构地区：[1]Laboratory of Cardiovascular Immunology, Institute of Cardiology, Union Hospital, Tongji Medical College, Huazhong Science ＆ Technology University, Wuhan 430022, China [2]These authors contributed equally to this work [3]Laboratory of Cardiovascular Immunology, Institute of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, 1277 Jiefang Road, Wuhan 430022, China.

出　　处：《Cellular & Molecular Immunology》2008年第3期209-217,共9页中国免疫学杂志（英文版）

基　　金：This work was funded by National Natural Science Foundation of China(Project No.30300133 and Project No.30600235).

摘　　要：Agonistic AT1 receptor autoantibodies （AT1-AAs） have been described in the patients with malignant hypertension or preeclampia. Furthermore, AT1-AAs were highly associated with refractory hypertension. Function of vascular smooth muscle cells （VSMCs） is important in the regulation of blood pressure. We investigated and compared the ability of angiotensin II （Ang II） and AT1-AAs to stimulate the intracellular calcium mobilization and cellular proliferation of rat VSMCs. Twenty-two patients with refractory hypertension, 24 patients with non-refractory hypertension and 37 normotensives were recruited. The serum of each patient was detected for the presence of AT1-AAs by ELISA. Ang II and the AT1-AAs from the sera of patients were used to stimulate rat VSMCs in vitro. AT1-AAs were detected in 10/22, 3/24 and 3/37 of patients with refractory hypertension, non-refractory hypertension and normotensives, respectively. AT1-AAs led the increase intracellular calcium mobilization in a dose-dependent manner and cellular proliferation of VSMCs just as Ang II. Both of these effects caused by AT1-AAs were blocked with losartan or a peptide corresponding to a part of the second extracellular loop of AT1 receptor. Since AT1-AAs exhibited pharmacological activity in rat VSMCs just as Ang II, they might play a role in the elevation of peripheral vascular resistance and in vascular remodeling. And AT1-AAs were suggested to involve in resistance to antihypertensive therapy.Agonistic AT1 receptor autoantibodies （AT1-AAs） have been described in the patients with malignant hypertension or preeclampia. Furthermore, AT1-AAs were highly associated with refractory hypertension. Function of vascular smooth muscle cells （VSMCs） is important in the regulation of blood pressure. We investigated and compared the ability of angiotensin II （Ang II） and AT1-AAs to stimulate the intracellular calcium mobilization and cellular proliferation of rat VSMCs. Twenty-two patients with refractory hypertension, 24 patients with non-refractory hypertension and 37 normotensives were recruited. The serum of each patient was detected for the presence of AT1-AAs by ELISA. Ang II and the AT1-AAs from the sera of patients were used to stimulate rat VSMCs in vitro. AT1-AAs were detected in 10/22, 3/24 and 3/37 of patients with refractory hypertension, non-refractory hypertension and normotensives, respectively. AT1-AAs led the increase intracellular calcium mobilization in a dose-dependent manner and cellular proliferation of VSMCs just as Ang II. Both of these effects caused by AT1-AAs were blocked with losartan or a peptide corresponding to a part of the second extracellular loop of AT1 receptor. Since AT1-AAs exhibited pharmacological activity in rat VSMCs just as Ang II, they might play a role in the elevation of peripheral vascular resistance and in vascular remodeling. And AT1-AAs were suggested to involve in resistance to antihypertensive therapy.

关 键 词：AUTOIMMUNITY antibody hypertension angiotensin II receptor type 1 

分 类 号：R36[医药卫生—病理学]