42 43 Inhibitory neurotransmitters, chiefly nitric oxide and vasoactive intestinal peptide, 44 increase cyclic nucleotide levels and inhibit muscle contraction via inhibition of MLC 45 kinase and activation of MLC phosphatase. H2S produced as an endogenous signalling 46 molecule synthesized mainly from L-cysteine via cystathionine-γ-lyase (CSE) and 47 cystathionine-β-synthase (CBS) regulate mus...

Hydrogen sulfide (H2S) is produced endogenously from L-cysteine by the actions of enzymes cystathionine γ-lyase (CSE) and cystathionine β-synthase (CBS). The role of these enzymes in the regulation of systemic blood pressure (SBP) is not yet clearly defined. In this study, we have examined the effect of chronic deficiency of endogenous H2S, which was induced by inhibitors of CSE and CBS, on SBP...

Using methodology developed herein, it is found that reactive persulfides and polysulfides are formed endogenously from both small molecule species and proteins in high amounts in mammalian cells and tissues. These reactive sulfur species were biosynthesized by two major sulfurtransferases: cystathionine β-synthase and cystathionine γ-lyase. Quantitation of these species indicates that high con...

Hydrogen sulfide (H2S) is an important gaseous signaling molecule in the cardiovascular system. In addition to free H2S, H2S can be oxidized to polysulfide which can be biologically active. Since the impact of H2S on endothelial solute barrier function is not known, we sought to determine whether H2S and its various metabolites affect endothelial permeability. In vitro permeability was evaluate...

OBJECTIVE To examine the hypothesis that hydrogen sulfide (H2S) regulates the colonic motility by modulating both L-type voltage-dependent calcium channels and large conductance Ca2+-activated K+ (BKCa) channels. METHODS Immunohistochemistry was performed on rat colonic samples to investigate the localization of the H2S-producing enzymes cystathionine-β-synthase (CBS) and cystathionine-γ-lyas...

H2S is produced mainly by two enzymes:cystathionine-β-synthase (CBS) and cystathionine-γ-lyase (CSE), using L-cysteine (L-Cys) as the substrate. In this study, we investigated the role of H2S in gastric accommodation using CBS(+/-) mice, immunohistochemistry, immunoblot, methylene blue assay, intragastric pressure (IGP) recording and electrical field stimulation (EFS). Mouse gastric fundus expr...

Hydrogen sulfide (H2S) is the most recently characterized autocrine/paracrine messenger implicated in the control of vascular tone. A series of coherent observations now document that this gas is a strong vasorelaxant and a determinant of blood pressure in experimental models. Targeted deletion of the gene encoding cystathionine-lyase (CSE). CSE, a key enzyme for H2S biosynthesis, reduces serum...

Activation of plasma membrane TGR5 receptors in enteroendocrine cells by bile acids is known to regulate gastrointestinal secretion and motility and glucose homeostasis. The endocrine functions of the gut are modulated by microenvironment of the distal gut predominantly by sulfur-reducing bacteria of the microbiota that produce H2S. However, the mechanisms involved in the release of peptide hor...

Hydrogen sulfide (H2S) is a colourless, flammable gas with a characteristic pungent smell. Until recently, the H2S literature was focused in the toxicology of this agent. Exposure to H2S concentrations lower than 100 ppm lead to eye irritation, sore throat, dizziness, nausea, shortness of breath, and chest tightness, while exposure to 1000 ppm or more causes central nervous system toxicity and ...

Over the last decade, hydrogen sulfide (H2S) has emerged as an important endogenous gasotransmitter in mammalian cells and tissues. Similar to the previously characterized gasotransmitters nitric oxide and carbon monoxide, H2S is produced by various enzymatic reactions and regulates a host of physiologic and pathophysiological processes in various cells and tissues. H2S levels are decreased in ...