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Updated: May 25, 2026
08:41
Assessment of Vascular Tone Responsiveness using Isolated Mesenteric Arteries with a Focus on Modulation by Perivascular Adipose Tissues
Published on: June 3, 2019
Long distance conduction of vasodilation: a passive or regenerative process?
1Department of Neuroscience, The John Curtin School of Medical Research, The Australian National University, Acton, ACT, Australia. caryl.hill@anu.edu.au
Microcirculation (New York, N.Y. : 1994)
|February 9, 2012
Summary
Scientists explored how blood vessels rapidly adjust blood flow to meet metabolic needs. Evidence suggests voltage-dependent calcium channels enable long-distance vasodilation through membrane potential changes, coordinating blood flow regulation.
Area of Science:
- Physiology
- Cardiovascular Research
- Cellular Electrophysiology
Background:
- Coordinating resistance arteries and arterioles to regulate tissue blood flow based on metabolic demand is a long-standing scientific challenge.
- The electrical events underlying this coordination have been investigated, raising questions about how vasodilation signals propagate long distances without significant signal loss.
Purpose of the Study:
- To review existing data on the long-distance conduction of vasodilation.
- To provide evidence for a proposed mechanism involving voltage-dependent calcium channels.
Main Methods:
- Review of pertinent experimental data.
- Analysis of the relationship between membrane potential and calcium entry.
- Examination of the role of voltage-dependent calcium channels in vascular tone control.
Main Results:
- The steep relationship between membrane potential and calcium entry through voltage-dependent calcium channels is a key factor.
- This relationship provides a plausible mechanism for the long-distance, non-attenuated conduction of vasodilation.
Conclusions:
- Voltage-dependent calcium channels play a crucial role in mediating vascular tone.
- A simple mechanism based on the electrical properties of these channels likely explains the coordinated regulation of tissue blood flow.
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