TRPV4 contributes to renal injury induced by angiotensin II in mice

To determine whether deletion of TRPV4 attenuates angiotensin II (Ang II)-induced renal injury, Ang II was infused systemically into wild type (WT) and TRPV4-null mutant (TRPV4-/-) mice for 4 weeks. Systolic blood pressure increased in Ang II-treated WT or TRPV4-/-mice with the similar degree (P>0.05). Ang II treatment increased urinary excretion of albumin and 8-isoprostane, and decreased creatinine clearance in both WT and TRPV4-/-mice with a greater magnitude in the former strain (P<0.05). Periodic acid-Schiff and Masson's trichrome staining showed that kidneys of Ang II-treated WT mice exhibited more severe glomerulosclerosis and tubulointerstitial injury compared with Ang II-treated TRPV4-/-mice (P<0.05). Hydroxyproline assay and F4/80-staining showed that renal collagen levels and monocyte/macrophage infiltration were greater in Ang II-treated WT mice compared with TRPV4-/-mice (P<0.05). Thus, our data show that deletion of TRPV4 alleviates renal injury in the absence of alteration in blood pressure...