Hydrogen sulfide (H(2)S) functions as a neuromodulator, but whether it modulates visceral perception and pain is unknown. Cystathionine beta-synthase (CBS) and cystathionine-gamma-lyase (CSE) mediate enzymatic generation of H(2)S in mammalian cells. Here we have investigated the role of H(2)S in modulating nociception to colorectal distension, a model that mimics some features of the irritable ...

Endogenous hydrogen sulfide (H(2)S) is naturally synthesized in various types of mammalian cells from l-cysteine in a reaction catalyzed by two enzymes, cystathionine-gamma-lyase (CSE) and/or cystathionine-beta-synthase. The latest studies have implied that H(2)S functions as a vasodilator and neurotransmitter. However, so far there is little information about the role played by H(2)S in system...

Hypoxic pulmonary vasoconstriction (HVC), an intrinsic and assumed ubiquitous response of mammalian pulmonary blood vessels, matches regional ventilation to perfusion via an unknown O(2)-sensing mechanism. Global pulmonary hypoxia experienced by individuals suffering from chronic obstructive pulmonary disease or numerous hypoventilation syndromes, including sleep apnea, often produces maladapti...

O2 chemoreceptors elicit cardiorespiratory reflexes in all vertebrates, but consensus on O2-sensing signal transduction mechanism(s) is lacking. We recently proposed that hydrogen sulfide (H2S) metabolism is involved in O2 sensing in vascular smooth muscle. Here, we examined the possibility that H2S is an O2 sensor in trout chemoreceptors where the first pair of gills is a primary site of aquat...

Hydrogen sulphide (H(2)S) is synthesized from L-cysteine via the action of cystathionine-gamma-lyase (CSE) and cystathionine-beta-synthase (CBS). We have earlier shown that H(2)S acts as a mediator of inflammation. However the mechanism remains unclear. In this study, we investigated the presence of H(2)S and the expression of H(2)S synthesizing enzymes, CSE and CBS, in isolated mouse pancreati...

Hydrogen sulfide (H(2)S), a novel endogenous gaseous bioactive substance, has recently been implicated in the regulation of cardiovascular and neuronal functions. However, its role in the control of renal function is unknown. In the present study, incubation of renal tissue homogenates with L-cysteine (L-Cys) (as a substrate) produced H(2)S in a concentration-dependent manner. This H(2)S produc...

BACKGROUND The present study was designed to explore the possible changes in endogenous hydrogen sulphide (H(2)S), a novel gasotransmitter, on the pathogenesis of allergic rhinitis (AR). METHODS AR guinea pig model was established by nasal ovalbumin sensitisation. Guinea pigs were divided into four groups: Saline control, AR sensitised, sodium hydrosulphide (NaHS) treated, and propargylglycin...

BACKGROUND Hydrogen sulphide is a gas signalling molecule which is produced endogenously from L-cysteine via the enzymes cystathionine beta-synthase (CBS) and cystathionine gamma-lyase (CSE). The possible role of hydrogen sulphide in reproduction has not yet been fully investigated. It has been previously demonstrated that hydrogen sulphide relaxes uterine smooth muscle in vitro. The aim of the...

The molecular and cellular mechanisms underlying plaque destabilization remain obscure. We sought to elucidate the correlation between NO, H2S and CO-generating enzymes, nitro-oxidative stress and plaque stability in carotid arteries. Carotid atherosclerotic plaques were collected from 62 patients who had undergone endarterectomy due to internal artery stenosis. Following histological evaluatio...

Hydrogen sulfide (H2S) is a recently identified gasotransmitter that may mediate hypoxic responses in vascular smooth muscle. H2S also appears to be a signaling molecule in mammalian non-vascular smooth muscle, but its existence and function in non-mammalian non-vascular smooth muscle have not been examined. In the present study we examined H2S production and its physiological effects in urinar...