Mechanisms of action of hydrogen sulfide in relaxation of mouse distal colonic smooth muscle
| Autor: | Inge Van Colen, Ingeborg Dhaese, Romain Lefebvre |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
Male
medicine.medical_specialty Thapsigargin Potassium Channels Colon Muscle Relaxation chemistry.chemical_element Calcium In Vitro Techniques Apamin Nervous System Ouabain chemistry.chemical_compound Mice Cytosol Internal medicine medicine Potassium Channel Blockers Animals Hydrogen Sulfide Enzyme Inhibitors Pharmacology Ryanodine receptor Muscle Smooth Potassium channel Endocrinology chemistry Myosin-light-chain phosphatase Capsazepine medicine.drug Muscle Contraction |
| Zdroj: | European journal of pharmacology. 628(1-3) |
| ISSN: | 1879-0712 |
| Popis: | Hydrogen sulfide (H(2)S) has been suggested as a gaseous neuromodulator in mammals. The aim of this study was to examine the influence of H(2)S on contractility in mouse distal colon. The effect of sodium hydrogen sulfide (NaHS; H(2)S donor) on prostaglandin F(2alpha) (PGF(2alpha))-contracted circular muscle strips of mouse distal colon was investigated. In addition, tension and cytosolic calcium concentration ([Ca(2+)](cyt)) in the mouse distal colon strips were measured simultaneously in the presence of NaHS. NaHS caused concentration-dependent relaxation of the pre-contracted mouse distal colon strips. The NaHS-induced relaxation was not influenced by the K(+) channels blockers glibenclamide, apamin, charybdotoxin, barium chloride and 4-aminopyridine. The relaxation by NaHS was also not influenced by the nitric oxide inhibitor L-NAME, by the soluble guanylate cyclase respectively adenylate cyclase inhibitors ODQ and SQ 22536, by the nerve blockers capsazepine, omega-conotoxin and tetrodotoxin or by several channel and receptor blockers (ouabain, nifedipine, 2-aminoethyl diphenylborinate, ryanodine and thapsigargin). The initiation of the NaHS-induced relaxation was accompanied by an increase in [Ca(2+)](cyt), but once the relaxation was maximal and sustained, no change in [Ca(2+)](cyt) was measured. This calcium desensitization is not related to the best known calcium desensitizing mechanism as the myosin light chain phosphatase (MLCP) inhibitor calyculin-A and the Rho-kinase inhibitor Y-27632 had no influence. We conclude that NaHS caused concentration-dependent relaxations in mouse distal colon not involving the major known K(+) channels and without a change in [Ca(2+)](cyt). This calcium desensitization is not related to inhibition of Rho-kinase or activation of MLCP. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect