ABSTRACT
The antibody against AT1-EC2 plays a role in some kinds of inflammatory vascular diseases including malignant hypertension, preeclampsia, and renal-allograft rejection, but the detailed mechanisms remain unclear. In order to investigate the changes of NADPH oxidase and reactive oxygen species in the aorta in a mouse model which can produce AT1-EC2 antibody by active immunization with AT1-EC2 peptide, 15 mice were divided into three groups: control group, AT1-EC2-immunized group, and AT1-EC2-immunized and valsartan-treated group. In AT1-EC2-immunized group and AT1-EC2-immunized and valsartan-treated group, the mice were immunized by 50 μg peptide subcutaneously at multiple points for 4 times: 0, 5, 10, and 15 days after the experiment. In AT1-EC2-immunized and valsartan-treated group, valsartan was given at a dose of 100 mg/kg every day for 20 days. After the experiment, the mice were sacrificed under anesthesia and the aortas were obtained and frozen in liquid nitrogen for the preparation of frozen section slides and other experiments. The titer of AT1-EC2 was assayed by using ELISA. The level of NOX1 mRNA in the aorta was determined by using RT-PCR. The expression of NOX1 was detected by using Western blotting. Confocal scanning microscopy was used to assay the α-actin and NOX1 expression in the aortic tissue. The O(2)∸ production was detected in situ after DHE staining. The mice produced high level antibody against AT1-EC2 in AT1-EC2-immunized group and AT1-EC2-immunized and valsartan-treated group, and the level of NOX1 mRNA in the aortic tissues was 1.6±0.4 times higher and the NOX1 protein expression was higher in AT1-EC2-immunized group than in control group. There were no significant differences in the level of NOX1 mRNA and protein expression between control group and AT1-EC2-immunized and valsartan-treated group. The expression and co-localization of α-actin and NOX1 in AT1-EC2-immunized group increased significantly as compared with those in control group, and the O(2)∸ production increased about 2.7 times as compared with control group. There were no significant differences between control group and AT1-EC2-immunized and valsartan-treated group. It is concluded that active immunization with AT1-EC2 can activate NOX1-ROS, and increase vascular inflammation, which can be inhibited by AT1 receptor blocker valsartan. This may partially explain the mechanism of the pathogenesis of inflammatory vascular diseases related to antibody against AT1-EC2.
ABSTRACT
The antibody against AT1-EC2 plays a role in some kinds of inflammatory vascular diseases including malignant hypertension, preeclampsia, and renal-allograft rejection, but the detailed mechanisms remain unclear. In order to investigate the changes of NADPH oxidase and reactive oxygen species in the aorta in a mouse model which can produce AT1-EC2 antibody by active immunization with AT1-EC2 peptide, 15 mice were divided into three groups: control group, AT1-EC2-immunized group, and AT1-EC2-immunized and valsartan-treated group. In AT1-EC2-immunized group and AT1-EC2-immunized and valsartan-treated group, the mice were immunized by 50 μg peptide subcutaneously at multiple points for 4 times: 0, 5, 10, and 15 days after the experiment. In AT1-EC2-immunized and valsartan-treated group, valsartan was given at a dose of 100 mg/kg every day for 20 days. After the experiment, the mice were sacrificed under anesthesia and the aortas were obtained and frozen in liquid nitrogen for the preparation of frozen section slides and other experiments. The titer of AT1-EC2 was assayed by using ELISA. The level of NOX1 mRNA in the aorta was determined by using RT-PCR. The expression of NOX1 was detected by using Western blotting. Confocal scanning microscopy was used to assay the α-actin and NOX1 expression in the aortic tissue. The O(2)∸ production was detected in situ after DHE staining. The mice produced high level antibody against AT1-EC2 in AT1-EC2-immunized group and AT1-EC2-immunized and valsartan-treated group, and the level of NOX1 mRNA in the aortic tissues was 1.6±0.4 times higher and the NOX1 protein expression was higher in AT1-EC2-immunized group than in control group. There were no significant differences in the level of NOX1 mRNA and protein expression between control group and AT1-EC2-immunized and valsartan-treated group. The expression and co-localization of α-actin and NOX1 in AT1-EC2-immunized group increased significantly as compared with those in control group, and the O(2)∸ production increased about 2.7 times as compared with control group. There were no significant differences between control group and AT1-EC2-immunized and valsartan-treated group. It is concluded that active immunization with AT1-EC2 can activate NOX1-ROS, and increase vascular inflammation, which can be inhibited by AT1 receptor blocker valsartan. This may partially explain the mechanism of the pathogenesis of inflammatory vascular diseases related to antibody against AT1-EC2.
Subject(s)
Animals , Mice , Aorta , Metabolism , Disease Models, Animal , Mice, Inbred C57BL , NADPH Oxidases , Genetics , Reactive Oxygen Species , Metabolism , Vaccination , MethodsABSTRACT
Objective To explore the role of the autoantibodies against ?_1-adrenergic receptor(?_1-receptor)in the development of hypertension with renal failure.Methods The epitopes of the second extracellular loop of ?_1-receptor were synthesized and used respectively to screen sera autoantibodies from patients with hypertension with renal failure(61 cases),hypertension without renal failure(58 cases) and healthy blood donors(40 cases,control) by ELISA method.Results The positive rates of the autoantibodies ?_1-receptor(69%,42/61) in patients with hypertension with renal failure were higher than those of patients with hypertension without renal failure(19%,11/58) respectively(P
ABSTRACT
Objective To explore the roles of autoantibodies against ?1 adrenoceptor(?1-receptor)and M2 cholinergic receptor(M2-receptor)in patients with chronic renal insufficiency.Methods The epitopes of the second extracellular loop of ?1 receptor and M2 receptor were synthesized and used respectively to detect the sera autoantibodies against ?1 receptor and M2 receptor by enzyme linked immunosorbent assay(ELISA) in 76 patients with chronic renal insufficiency,60 cases with hypertension and 40 healthy controls.Results In patients with chronic renal insufficiency,the positive rates of the autoantibodies against ?1-receptor and M2-receptor were 56.7% and 38.1% respectively,which were much higher than those of patients with hypertension(18.3% and 11.7%) and higher than those of healthy controls(17.5% and 15.0%)(all P
ABSTRACT
Objective To explore the role of the autoantibodies against ?_1 and ?_1-adrenergic receptor(?_1-receptor)in the development of hypertension with renal failure.Methods The epitopes of the second extracellular loop of ?_1-receptor(197-222) and ?_1-receptor(192-218) were synthesized and used respectively to screen sera autoantibodies in patients with hypertension and renal failure(n=61),hypertension without renal failure(n=60) and healthy blood donors(n=40,control) by ELISA.Results The positive rates of the autoantibodies against ?_1-receptor(62.3%)and ?_1 receptor(50.8%) in patients with hypertension with renal failure were higher than those of patients with hypertension without renal failure(13.3% and10.0%)(P
ABSTRACT
AIM: The autoantibodies against ?_1-adrenergic receptor that was found in patients with malignant hypertension, primary hypertension and refractory hypertension has the agonist activity liked the NE, and may play a role in hypertension. In this paper, the effects of this antibody on vascular smooth muscle cell (VSMC) proliferation and its mechanism were to be studied. METHODS: The cultured rat VSMC proliferation induced by the antibodies against ?_1- adrenergic receptor that was purified by the immune affinity chromatography, was measured by the BrdU cell proliferation assay and cell cycle distribution. The expression of c-jun and c-fos were determined by RT-PCR and Western blotting. RESULTS: Compared to the normal IgG, the antibodies against ?_1-adrenergic receptor promoted the VSMC proliferation and increased the mRNA and protein expression of the c-jun significantly. The role was similar to the norepinephrine, and all was blocked by prazosin, while the mRNA and protein expression of c-fos were not affected by the antibodies. CONCLUSION: The antibodies against ?_1-adrenergic receptor promote the rat VSMC proliferation, and increase the expression of c-jun, which maybe play a role in the vascular remodeling in hypertension.