MAS1 and chronic kidney disease: The major contributions of our study are summarized as follows: (1) STS treatment attenuated the elevation of BP in rats with adenine-induced CKD, (2) CKD caused a reduction in renal H2S-generating enzyme expression, while STS treatment had a negligible effect on their levels, (3) STS therapy increased plasma levels of H2S and thiosulfate, (4) the beneficial effect of STS was associated with the reduction of ADMA and the restoration of L-Arginine-to-ADMA ratio in the plasma, and (5) STS treatment enhanced RAS gene Ace2 and Mas1 but decreased Agtr1a.