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Assessment of Vascular Tone Responsiveness using Isolated Mesenteric Arteries with a Focus on Modulation by Perivascular Adipose Tissues
Published on: June 3, 2019
Adenosine A(1) receptors and vascular reactivity
1Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Acta Physiologica (Oxford, England)
|February 6, 2010
Summary
Blood pressure is higher in adenosine A(1) receptor knock-out mice. Vascular function differences did not fully explain this, suggesting extravascular factors are key to A(1) receptor blood pressure modulation.
Area of Science:
- Cardiovascular Physiology
- Pharmacology
- Molecular Biology
Background:
- Adenosine A(1) receptors (A(1)R) play a role in cardiovascular regulation.
- A(1)R knock-out (A(1)R-/-) mice exhibit higher blood pressure than wild-type (A(1)R+/+) littermates.
Purpose of the Study:
- To investigate if elevated blood pressure in A(1)R-/- mice is linked to altered vascular function.
- To determine the specific role of adenosine A(1) receptors in vascular tone regulation.
Main Methods:
- Examined contraction of isolated aortic rings and mesenteric arteries.
- Measured pulse pressure (PP) and augmentation index (AIX) in vivo.
- Utilized adenosine receptor agonists and antagonists to assess receptor function.
Main Results:
- Vascular responses to phenylephrine and acetylcholine were similar between genotypes.
- A(1)R-/- mice showed impaired A(1)R-mediated contraction in aortic rings.
- Adenosine-mediated vasorelaxation was similar in mesenteric arteries, implicating A(2B) receptors.
- Higher PP in A(1)R-/- mice was observed, but AIX did not differ significantly.
Conclusions:
- Adenosine A(1) receptor function in regulating vascular tone varies across different blood vessels.
- Contractile effects in isolated vessels do not fully account for the higher blood pressure in A(1)R-/- mice.
- Extravascular factors are likely the primary mediators of A(1) receptor's influence on blood pressure.
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