title: Cellular mechanism underlying the facilitation of contractile response of vas deferens smooth muscle by sodium orthovanadate.
abstract: In the earlier study, sodium orthovanadate (SOV) has been reported to be a powerful inhibitor of (Na(+), K(+)) adenosine triphosphatase, exhibit widespread actions on the renal and cardiovascular systems, induces smooth muscle contraction by inhibiting the phosphorylation of the protein tyrosine phosphatases. In the current study, we aimed to investigate the cellular mechanisms by which SOV facilitated contractile response of vas deferens smooth muscle and its potential therapeutic advantage. Exogenous application of ATP and NA-caused contraction was strengthened by pretreatment with SOV. This facilitation was inhibited not by bath with the inhibitor of P2 receptor, PPADS, or the inhibitor of α1 receptor, Prazosin, but by bath with the protein tyrosine kinase inhibitor, Genistein. SOV induced a sustained increase in intracellular Ca(2+) of smooth muscle cells, which was abolished by 100 μM Genistein or Ca(2+)-free solution. The facilitation of SOV could also be inhibited by the selective inhibitors of TRP channel, 2-APB and non-selective cation channel, Gd(3+), Ni(+). The in vivo study showed that peritoneal injection of SOV in dystrophic mice (mdx mice) enhanced the contraction of vas deferens smooth muscle stimulated by electrical field stimulation, ATP, noradrenaline, or KCl. The above results suggest that SOV facilitates the concentration of vas deferens smooth muscle through the tyrosine phosphorylation activated the non-selective cation channels, which has potential use in the therapy for muscle dysfunction.
authors.affiliation: Department of Physiology, Guangzhou Medical University, 195 Dongfeng West Road, Guangzhou 510182, People's Republic of China. crystal-zl@163.com
authors.forename: Lei
authors.initials: L
authors.lastname: Zhao
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
authors.forename: Ye-Chun
authors.initials: YC
authors.lastname: Ruan
authors.forename: Wen-Liang
authors.initials: WL
authors.lastname: Zhou
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D058668:Adrenergic alpha-1 Receptor Antagonists; D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000818:Animals; D001896:Boron Compounds / Q000494:pharmacology; D020013:Calcium Signaling / Q000187:drug effects; D002478:Cells, Cultured; D004347:Drug Interactions; D004558:Electric Stimulation; D019833:Genistein / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D018101:Mice, Inbred mdx; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D009638:Norepinephrine / Q000494:pharmacology; D018408:Patch-Clamp Techniques; D011224:Prazosin / Q000494:pharmacology; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D050051:Transient Receptor Potential Channels / Q000819:agonists / Q000037:antagonists & inhibitors; D014638:Vanadates / Q000494:pharmacology*; D014649:Vas Deferens / Q000166:cytology / Q000502:physiology*
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D000316:Adrenergic alpha-Agonists; D001896:Boron Compounds; D047428:Protein Kinase Inhibitors; D050051:Transient Receptor Potential Channels; D014638:Vanadates; D000255:Adenosine Triphosphate; D019833:Genistein; C109986:2-aminoethoxydiphenyl borate; D009638:Norepinephrine; D011224:Prazosin