Different roles of specific ROS in regulation of myogenic contractions in microarterioles

Christopher-Wilcox-Redox-2019The Scientific Committee of Paris Redox 2019 will be welcoming Prof. Christopher Wilcox, Chief of the Georgetown Nephrology and Hypertension, Director of the Center for Hypertension Research, Georgetown University, USA.

Dr. Wilcox will be presenting his studies entitled "Roles of hydrogen peroxide and superoxide in myogenic responses of cerebral and renal microarterioles in hypertensive mice".

ROS have established pathophysiological roles but an understanding of their normal physiological actions is essential in planning safe and effective therapy. Myogenic contractions protect the brain and kidneys from hypertensive barotrauma. We have contrasted the effect of hydrogen peroxide with superoxide (O2∙-) on myogenic contractions of single microarterioles isolated from the intracerebral cortex or the renal cortex of gene manipulated mice and perfused at controlled pressures. We found that normal myogenic contractions depended on O2∙- generated from p47phox/NOX2 but were impaired in cerebral microarterioles selectively in hypertension by excessive H2O2 generated by POLDIP2/NOX4. Thus, ROS have divergent effects on myogenic contractions: O2∙- is required for normal protection of the kidneys and brain from barotrauma but this is overridden by H2O2 generated specifically in cerebral microarterioles during hypertension.

For more information about Paris Redox 2019: www.isanh.net.