Modulation of endogenous production of H2S in rat tissues

Abstract

H 2 S is an important gasotransmitter with a vasorelaxant property. The modulation of endogenous H 2 S generation from different tissues and the functional consequence of this modulation are not clear. In the present study, the production of H 2 S from vascular tissues as well as the liver and ileum of rats was measured. The H 2 S production rate was significantly greater in rat liver than rat vascular tissues. H 2 S production in rat aortae, ileum, and liver tissues was upregulated by sodium nitroprusside in a cGMP-dependent fashion. Amino-oxyacetate (AOA) (1 mM) abolished H 2 S production in liver tissues and partially inhibited H 2 S production in the ileum, while D,L-propargylglycine (PPG) at a similar concentration only slightly inhibited H 2 S production in liver. Intraperitoneal injection PPG, but not AOA, significantly suppressed H 2 S production in liver, aorta, and ileum tissues. The systolic blood pressure of rats was significantly increased 2–3 weeks after i.p. injection of PPG. It is concluded that the endogenous production of H 2 S could be modulated by NO. AOA and PPG have different capacities in regulating the endogenous production of H 2 S in different types of tissues.Key words: gasotransmitter, cGMP, hydrogen sulfide, nitric oxide, vascular tissues.