TY - JOUR
T1 - Pharmacological actions of the slow release hydrogen sulfide donor GYY4137 on phenylephrine-induced tone in isolated bovine ciliary artery
AU - Chitnis, Madhura Kulkarni
AU - Njie-Mbye, Ya Fatou
AU - Opere, Catherine A.
AU - Wood, Mark E.
AU - Whiteman, Matthew
AU - Ohia, Sunny E.
PY - 2013/11
Y1 - 2013/11
N2 - Hydrogen sulfide (H2S), a colorless gas characterized by its pungent odor of rotten eggs has been reported to elicit relaxation effects on basal and pre-contracted non-ocular smooth muscles of several mammalian species. In the present study, we investigated the pharmacological actions of a H2S donor, GYY4137 on isolated bovine posterior ciliary artery after contraction with the adrenergic receptor agonist, phenylephrine. Furthermore, we studied the underlying mechanism of inhibitory action of GYY4137 on the posterior ciliary arteries. Isolated bovine posterior ciliary arteries were mounted in oxygenated organ baths and changes in isometric tension were measured with a Grass FT03 transducer connected to a recorder using a Grass Polyview Software. The relaxant actions of GYY4137 on phenylephrine pre-contracted arteries were observed in the absence and presence of an inhibitor of cyclo-oxygenase, flurbiprofen. Furthermore, the inhibitory effects of GYY4137 were studied in the absence or presence of inhibitors/activators of biosynthetic enzymes for H2S and nitric oxide production, as well as specific ion channel blockers. In the concentration range, 100nM to 100μM, GYY4137 elicited a concentration-dependant relaxation of phenylephrine-induced tone in isolated posterior ciliary arteries, with IC50 value of 13.4±1.9μM (n=6). The cyclo-oxygenase inhibitor, flurbiprofen, significantly (p50 value of 0.13±0.08μM (n=6). Both the inhibitors of cystathionine β-synthase (aminooxyacetic acid, AOAA, 30μM) and cystathionine γ-lyase (propargylglycine, PAG, 1mM) caused significant (pATP channel antagonist, glibenclamide (100μM) significantly (p2S. Furthermore, the observed vascular smooth muscle relaxation induced by GYY4137 is mediated, at least in part, by KATP channels.
AB - Hydrogen sulfide (H2S), a colorless gas characterized by its pungent odor of rotten eggs has been reported to elicit relaxation effects on basal and pre-contracted non-ocular smooth muscles of several mammalian species. In the present study, we investigated the pharmacological actions of a H2S donor, GYY4137 on isolated bovine posterior ciliary artery after contraction with the adrenergic receptor agonist, phenylephrine. Furthermore, we studied the underlying mechanism of inhibitory action of GYY4137 on the posterior ciliary arteries. Isolated bovine posterior ciliary arteries were mounted in oxygenated organ baths and changes in isometric tension were measured with a Grass FT03 transducer connected to a recorder using a Grass Polyview Software. The relaxant actions of GYY4137 on phenylephrine pre-contracted arteries were observed in the absence and presence of an inhibitor of cyclo-oxygenase, flurbiprofen. Furthermore, the inhibitory effects of GYY4137 were studied in the absence or presence of inhibitors/activators of biosynthetic enzymes for H2S and nitric oxide production, as well as specific ion channel blockers. In the concentration range, 100nM to 100μM, GYY4137 elicited a concentration-dependant relaxation of phenylephrine-induced tone in isolated posterior ciliary arteries, with IC50 value of 13.4±1.9μM (n=6). The cyclo-oxygenase inhibitor, flurbiprofen, significantly (p50 value of 0.13±0.08μM (n=6). Both the inhibitors of cystathionine β-synthase (aminooxyacetic acid, AOAA, 30μM) and cystathionine γ-lyase (propargylglycine, PAG, 1mM) caused significant (pATP channel antagonist, glibenclamide (100μM) significantly (p2S. Furthermore, the observed vascular smooth muscle relaxation induced by GYY4137 is mediated, at least in part, by KATP channels.
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U2 - 10.1016/j.exer.2013.10.004
DO - 10.1016/j.exer.2013.10.004
M3 - Article
C2 - 24145109
AN - SCOPUS:84887207524
VL - 116
SP - 350
EP - 354
JO - Experimental Eye Research
JF - Experimental Eye Research
SN - 0014-4835
ER -