Piezo1 Mechanotransduction in the Uterine Circulation

Is the Piezo1 cation channel the sensor for shear stress that triggers uterine blood vessel growth and vasodilation in pregnancy? Listen as Editor in Chief Irving H. Zucker (University of Nebraska Medical Center) interviews lead author George Osol (University of Vermont College of Medicine) and content expert Kirk Conrad (University of Florida University of Florida College of Medicine) about the new study by John et al that explores the presence of Piezo1 in the uterine circulation, and the channel’s response to shear stress and the link to nitric oxide in both pregnant and non-pregnant uterine arteries. In the context of pregnancy, might a defect in Piezo1 expression or physiology trigger trophoblast invasion and spiral artery remodeling which lead to preeclampsia? Listen and learn more.

 

Liam John, Nga Ling Ko, Alexander Gokin, Natalia Gokina, Maurizio Mandala, and George Osol The Piezo1 Cation Channel Mediates Uterine Artery Shear Stress Mechanotransduction and Vasodilation During Rat Pregnancy Am J Physiol Heart Circ Physiol, published July 13, 2018. DOI: 10.1152/ajpheart.00103.2018

Vascular Smooth Muscle Actin Depolymerization

Is actin depolymerization the mechanism that causes vasodilation in small resistance arterioles? Listen as Associate Editor Robert Hester (University of Mississippi Medical Center) and content expert William Jackson (Michigan State University) interview lead author Philip Clifford (University of Illinois at Chicago) about the new study by Clifford et al. Using two different vasodilators with two different mechanisms of action, Clifford and co-authors found that there was an increase in the G-actin to sm22apha ratio, signaling a reduction in the amount of F-actin in the cell. Both vasodilators investigated-- pinacidil and sodium nitroprusside—act partially through an actin depolymerization. However, sodium nitroprusside is more dependent on this mechanism to achieve vasodilation. What is the time course of this change in actin polymerization? Is depolymerization essential for vasodilation, or a by-product of vasodilation? Listen to our experts and find out.

 

Philip S. Clifford, Brian S. Ferguson, Jeffrey L. Jasperse, and Michael A. Hill Arteriolar vasodilation involves actin depolymerization Am J Physiol Heart Circ Physiol, published August 8, 2018. DOI: 10.1152/ajpheart.00723.2017