PTGS2 and renovascular hypertension: From a mechanistic point of view, H2S improves endothelial function through the inhibition of oxidative stress, suppression of renin angiotensin system, downregulation of bone morphogenic protein 4/cyclooxygenase-2 (BMP4/COX-2) pathway, or activation of the PPARδ/PI-3K/Akt/AMPK/eNOS cascade, thus contributing to the antihypertensive mechanism of H2S in renovascular hypertensive rats [91,92,93].