Staff Members - Benha University
ATP-induced contraction in smooth muscle of chicken anterior mesenteric artery involves both pharmacomechanical and electromechanical couplings via activation of P2X receptor.
Molecular & Clinical Pharmacology • 2012
Publication Information
Authors
21. Marwan Draid, AbuBakr El-Mahmoudy, Yasutake Shimizu, Takahiko Shiina, Tadashi Takewaki.
Keywords
ATP; Chicken; Mesenteric artery; Membrane potential; Contraction
Journal
Molecular & Clinical Pharmacology
Publisher
Inforsights Publishing
Volume
3
Issue
1
Pages
40-46.
publication.type
International
Paper Link
Not Available
Supplementary Materials
Not Available
Abstract
The relationship between ATP-induced membrane potential and contraction was
investigated in the smooth muscle of chicken anterior mesenteric artery using microelectrode
and tension recording techniques respectively. Application of ATP to endothelium-
denuded arterial preparations developed concentration-dependent, slow
depolarization which started only at concentrations not less than 10 μM. On the
other hand the tension recording experiment revealed that ATP produced concentration-
dependent contractions, which were evident at concentrations lower than
those evoked depolarizing response to ATP (as lower 100 nM). Both depolarizing
& contracting responses were abolished by the P2X receptor blocker, PPADS (50
μM) but not by P2Y receptor blocker CBF3GA (100 μM), indicating that the
excitatory responses of ATP were mediated via activation of P2X receptor. These
findings suggest that ATP-mediated contraction is not dependent on membrane
depolarization only, at least at low concentrations in the first order branches of chicken
anterior mesenteric artery.
investigated in the smooth muscle of chicken anterior mesenteric artery using microelectrode
and tension recording techniques respectively. Application of ATP to endothelium-
denuded arterial preparations developed concentration-dependent, slow
depolarization which started only at concentrations not less than 10 μM. On the
other hand the tension recording experiment revealed that ATP produced concentration-
dependent contractions, which were evident at concentrations lower than
those evoked depolarizing response to ATP (as lower 100 nM). Both depolarizing
& contracting responses were abolished by the P2X receptor blocker, PPADS (50
μM) but not by P2Y receptor blocker CBF3GA (100 μM), indicating that the
excitatory responses of ATP were mediated via activation of P2X receptor. These
findings suggest that ATP-mediated contraction is not dependent on membrane
depolarization only, at least at low concentrations in the first order branches of chicken
anterior mesenteric artery.