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Hydrogen sulfide-induced relaxation of resistance mesenteric artery beds of rats.
| Content Provider | Semantic Scholar |
|---|---|
| Author | Cheng, Youqin Ndisang, Joseph Fomusi Tang, Guanghua Wang, Rui |
| Copyright Year | 2004 |
| Abstract | Hydrogen sulfide (H2S) has been shown recently to function as an important gasotransmitter. The present study investigated the vascular effects of H2S, both exogenously applied and endogenously generated, on resistance mesenteric arteries of rats and the underlying mechanisms. Both H2S and NaHS evoked concentration-dependent relaxation of in vitro perfused rat mesenteric artery beds (MAB). The sensitivity of MAB to H2S (EC50, 25.2 +/- 3.6 microM) was about fivefold higher than that of rat aortic tissues. Removal of endothelium or coapplication of charybdotoxin and apamin to endothelium-intact MAB significantly reduced the vasorelaxation effects of H2S. The H2S-induced relaxation of MAB was partially mediated by ATP-sensitive K+ (KATP) channel activity in vascular smooth muscle cells. Pinacidil (EC50, 1.7 +/- 0.1 microM, n=6) mimicked, but glibenclamide (10 microM, n=6) suppressed, the vasorelaxant effect of H2S. KATP channel currents in isolated mesenteric artery smooth muscle cells were significantly augmented by H2S. L-cysteine, a substrate of cystathionine-gamma-lyase (CSE), at 1 mM increased endogenous H2S production by sixfold in rat mesenteric artery tissues and decreased contractility of MAB. DL-propargylglycine (a blocker of CSE) at 10 microM abolished L-cysteine-dependent increase in H2S production and relaxation of MAB. Our results demonstrated a tissue-specific relaxant response of resistance arteries to H2S. The stimulation of KATP channels in vascular smooth muscle cells and charybdotoxin/apamin-sensitive K+ channels in vascular endothelium by H2S represents important cellular mechanisms for H2S effect on MAB. Our study also demonstrated that endogenous CSE can generate sufficient H2S from exogenous L-cysteine to cause vasodilation. Future studies are merited to investigate direct contribution of endogenous H2S to regulation of vascular tone. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://ajpheart.physiology.org/content/ajpheart/287/5/h2316.full.pdf |
| Alternate Webpage(s) | http://ajpheart.physiology.org/content/ajpheart/287/5/H2316.full.pdf |
| PubMed reference number | 15191893v1 |
| Volume Number | 287 |
| Issue Number | 5 |
| Journal | American journal of physiology. Heart and circulatory physiology |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Adenosine Triphosphate Apamin Arterial system Artery Smooth Muscle Tissue Beds Body tissue Carotid Stenosis Charybdotoxin Cystathionine Endothelium, Vascular Glyburide Hydrogen Sulfide KATP Channels Lindane Lyase Mesenteric Arteries Mesentery Muscle Cells Muscle, Smooth, Vascular Myocytes, Smooth Muscle Pinacidil SIAE gene Smooth muscle (tissue) Sulfides Vasodilation disorder channel activity peptidyl-L-cysteine methyl disulfide biosynthetic process from peptidyl-cysteine propargylglycine sodium bisulfide |
| Content Type | Text |
| Resource Type | Article |
