The methionine connection: Homocysteine and hydrogen sulfide exert opposite effects on hepatic microcirculation in rats
Eleonora Distrutti, Andrea Mencarelli, Luca Santucci, Barbara Renga, Stefano Orlandi, Annibale Donini, Vijay Shah, Stefano Fiorucci – 26 January 2008 – Increased intrahepatic resistance in cirrhotic livers is caused by endothelial dysfunction and impaired formation of two gaseous vasodilators, nitric oxide (NO) and hydrogen sulfide (H2S). Homocysteine, a sulfur‐containing amino acid and H2S precursor, is formed from hepatic methionine metabolism. In the systemic circulation, hyperhomocystenemia impairs vasodilation and NO production from endothelial cells.