EFFECT OF REACTIVE OXYGEN ON MECHANISMS COUPLING EXCITATION OF SMOOTH MUSCLE CELLS GUINEA PIG URETER: PP.21.345

Abstract

Objective: Reactive oxygen species claim to the role of signaling molecules, especially towards the realization of oxidative stress. However, the methods and extent of their interaction with key intracellular signaling and effector systems of regulation of excitation-coupling in smooth muscle cells continue to actively explored. This study examines the effect of reactive oxygen species in the mechanisms of regulation by cyclic nucleotides and calcium signaling system of electrical and contractile activity of smooth muscle cells. Design and Methods: The method of double sucrose bridge to study the effect of hydrogen peroxide and nitric oxide on electrical and contractile properties of smooth muscle cells of guinea pig ureter, caused by electric stimulus. To investigate the role of C-kinase branch of the calcium and nitric oxide in the development of the action potential and contractile responses of smooth muscle using phenylephrine and sodium nitroprusside, respectively. Results: Found opposite effect of hydrogen peroxide and cyclic nucleotides on C-kinase branch of the regulation of excitation-coupling in smooth muscle cells. With additional activation protenkinase with phenylephrine changing effects of hydrogen peroxide and sodium nitroprusside: electrical and contractile activity are inhibited. Similar effects have evolved against the background of inhibitors of enzymes break down hydrogen peroxide and cyclic nucleotides. Thus, the C-kinase branch of the calcium signaling system is one of the major intracellular targets, the effect on reactive oxygen species that leads to the inhibition of electrical and contractile activity of smooth muscle cells of guinea pig ureter.