Losartan protects against intermittent hypoxia-induced peritubular capillary loss by modulating the renal renin-angiotensin system and angiogenesis factors.

Losartan protects against intermittent hypoxia-induced peritubular capillary loss by modulating the renal renin-angiotensin system and angiogenesis factors. Acta Biochim Biophys Sin (Shanghai). 2019 Dec 14;: Authors: Wu J, Chu Y, Jiang Z, Yu Q Abstract Obstructive sleep apnea is characterized by chronic intermittent hypoxia (CIH), which is a risk factor for renal peritubular capillary (PTC) loss, and angiotensin II receptor blockers can alleviate PTC loss. However, the mechanism by which losartan (an angiotensin II receptor blocker) reduces CIH-induced PTC loss and attenuates kidney damage is still unknown. Thus, in this study, we examined the protective effects of losartan against CIH-induced PTC loss and explored the underlying mechanisms in rat CIH model. The immunohistochemical staining of CD34 and morphological examination showed that CIH reduced PTC density and damaged tubular epithelial cells. Immunohistochemistry, enzyme-linked immunosorbent assay (ELISA), real-time quantitative PCR, and western blot analysis results revealed that CIH increased the expression of hypoxia inducible factor-1α (HIF-1α), angiotensin II (Ang II), angiotensin II type 1 receptor (AT1R), pro-angiogenesis factor vascular endothelial growth factor (VEGF), and anti-angiogenesis factor thrombospondin-1 (TSP-1) in the renal cortex of rats. CIH may up-regulate VEGF expression and simultaneously increase TSP-1 production. By histopathological, immunohistoc...
Source: Acta Biochimica et Biophysica Sinica - Category: Biochemistry Authors: Tags: Acta Biochim Biophys Sin (Shanghai) Source Type: research