Effect of shear stress on surface membrane potassium ion permeability of calf pulmonary artery endothelial cells (Potassium ion)
type: CreativeWork
description: This study aims to determine the effect of shear stress on membrane potassium (K$\sp+$) permeability in vascular endothelial cells. Cultured monolayers of calf pulmonary artery endothelial cells, preloaded with $\rm \sp{86}Rb\sp+$, were subjected to different levels of fluid shear stress in the range 1-10 dynes/cm$\sp2$, in a parallel-plate geometry flow chamber, and the radioactivity of the effluent was monitored with time. Increase in laminar shear stress, from 1 dyne/cm$\sp2$ to a higher level, resulted in a rapid transient increase in the rate constant for $\rm \sp{86}Rb\sp+$ release. The difference of efflux rate coefficients, between the peak and the baseline at 1 dyne/cm$\sp2$, varied with shear stress in a "dose-dependent" manner. Changes in K$\sp+$ permeability may occur via activation of shear-stress-activated K$\sp+$ channels, Ca$\sp{2+}$-activated K$\sp+$ channels, or both. The Ca$\sp{2+}$-activated K$\sp+$ channels were shown to respond to bradykinin stimulation under flow conditions. The significance of such flow studies is that they provide more knowledge about the flow-associated changes in ionic channels and intracellular second messengers in endothelial cells.
abstract: This study aims to determine the effect of shear stress on membrane potassium (K$\sp+$) permeability in vascular endothelial cells. Cultured monolayers of calf pulmonary artery endothelial cells, preloaded with $\rm \sp{86}Rb\sp+$, were subjected to different levels of fluid shear stress in the range 1-10 dynes/cm$\sp2$, in a parallel-plate geometry flow chamber, and the radioactivity of the effluent was monitored with time. Increase in laminar shear stress, from 1 dyne/cm$\sp2$ to a higher level, resulted in a rapid transient increase in the rate constant for $\rm \sp{86}Rb\sp+$ release. The difference of efflux rate coefficients, between the peak and the baseline at 1 dyne/cm$\sp2$, varied with shear stress in a "dose-dependent" manner. Changes in K$\sp+$ permeability may occur via activation of shear-stress-activated K$\sp+$ channels, Ca$\sp{2+}$-activated K$\sp+$ channels, or both. The Ca$\sp{2+}$-activated K$\sp+$ channels were shown to respond to bradykinin stimulation under flow conditions. The significance of such flow studies is that they provide more knowledge about the flow-associated changes in ionic channels and intracellular second messengers in endothelial cells.
author: Alevriadou, Barbara Rita
language: eng
keywords: Biomedical engineering, Chemical engineering
date published: 1989
date modified: 2026-07-24T04:10:24Z
provider: Rice University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Rice University

PropertyValue
property ID: Handle
value: https://hdl.handle.net/1911/13339