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Updated: May 22, 2026
13:05
Micropatterning and Assembly of 3D Microvessels
Published on: September 9, 2016
Endothelial feedback and the myoendothelial projection
Paul M Kerr1, Raymond Tam, Katarina Ondrusova
1Faculty of Health and Community Studies, MacEwan University, Robbins Health Learning Centre, Edmonton, Alberta, Canada.
Microcirculation (New York, N.Y. : 1994)
|April 27, 2012
Summary
Myoendothelial feedback involves communication between smooth muscle and endothelial cells in resistance arteries. Evidence suggests that endothelial-derived hyperpolarization (EDH) is the primary mediator, not nitric oxide (NO).
Area of Science:
- Vascular biology
- Cardiovascular physiology
- Endothelial function
Background:
- The endothelium regulates resistance artery diameter, influencing blood flow and pressure.
- Endothelial cells release relaxing factors (e.g., nitric oxide) and mediate hyperpolarization (EDH) via gap junctions.
- Myoendothelial feedback, where smooth muscle contraction activates the endothelium, is crucial but less understood.
Purpose of the Study:
- To review recent data on the functional role of myoendothelial projections in smooth muscle-to-endothelial communication.
- To discuss evidence supporting the primary mediator of myoendothelial feedback in resistance arteries.
Main Methods:
- Review of recent scientific literature and data.
- Analysis of functional evidence for myoendothelial communication pathways.
Main Results:
- Recent evidence supports myoendothelial projections facilitating communication between smooth muscle and endothelial cells.
- Inositol trisphosphate (IP3) flux and localized calcium events within myoendothelial projections are implicated.
- Endothelial-derived hyperpolarization (EDH) appears to be the primary mediator of myoendothelial feedback.
Conclusions:
- Myoendothelial projections play a functional role in inter-cellular communication within resistance arteries.
- Endothelial-derived hyperpolarization (EDH) is the principal mediator of myoendothelial feedback, surpassing nitric oxide (NO).
- Understanding this feedback mechanism is vital for comprehending vascular tone regulation.
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