Effects of captopril on Klotho protein in hypertensive rats / 西安交通大学学报(医学版)

ABSTRACT

Objective: To evaluate the effects of captopril on Klotho protein and related inflammatory factors in the model of hypertensive SD rats. Methods: Eighteen SD rats were randomly divided into normal group, hypertensive model group and captopril experimental group, respectively. N'-nitro-L-arginine (L-NNA) was used by gavage in SD rats to make the hypertensive model. After successful establishment of the model, the experimental group was given captopril for treatment of hypertension, and the normal group and hypertension group were given an equal volume of normal saline by gavage in the SD rats. Blood pressure changes were measured by tail arteries of the SD rats. Enzyme-linked immunosorbent assay (ELISA) was used to measure plasma levels of Klotho protein, thromboxane (TXA2), and endothelin (ET). The level of nitric oxide (NO) was measured by nitrate reductase method. The content of malondialdehyde (MDA) was measured by TBA method, and the activity of superoxide dismutase (SOD) was measured by WST-1 method. The pathological changes of HE stained vascular wall in thoracic aorta of each group were observed. The vascular endothelial cell injury was evaluated by measuring the expression of CD31 by immunohistochemistry (IHC). Results: Compared with those in the normal group, the contents of TXA2, ET and MDA in the model group were significantly higher (P<0.05), while the content of Klothoprotein and NO and SOD activities were lower (P<0.05). Compared with those in the model group, the contents of TXA2, ET and MDA in the captopril group were significantly decreased (P<0.05), and the Klotho protein content, NO content and SOD activity were higher (P<0.05). The results of HE staining showed that the aortic vascular fibrosis and disorder in the model group and the aorticl wall were thicker than those in the normal group. The vessel wall was significantly thinner in the treatment group than in the model group. The results of IHC showed that the aortic endothelial cells in the model group were damaged and shedding. The vascular endothelial cells in the controlled group were increased and gradually repaired. Conclusion: Captopril can reduce the stress response of endothelial cells and repair the vascular endothelium, which can improve vascular endothelial function and increase Klotho protein level.