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Updated: Jun 4, 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
Aging attenuates the vasodilator response to relaxin
Joris van Drongelen1, Ivo H J Ploemen, Jeanne Pertijs
1Dept. of Obstetrics and Gynecology, Nijmegen Medical Centre, 6500 HB Nijmegen, The Netherlands. j.vandrongelen@obgyn.umcn.nl
American Journal of Physiology. Heart and Circulatory Physiology
|February 22, 2011
Summary
Aging impairs the body's response to relaxin, a peptide hormone crucial for pregnancy adaptations. Moderate aging reduces relaxin's ability to improve blood vessel function, potentially impacting vascular health.
Area of Science:
- Reproductive biology
- Vascular physiology
- Aging research
Background:
- Relaxin peptide hormone is vital for physiological circulatory adaptations during pregnancy, particularly in mesenteric and renal vasculature.
- Aging is linked to vascular maladaptation and increased risk of gestational hypertensive disorders.
- Previous research suggests relaxin influences vasodilation, vascular compliance, and myogenic reactivity.
Purpose of the Study:
- To investigate the hypothesis that mild aging reduces vascular responses to relaxin.
- To compare the effects of chronic relaxin exposure on vascular parameters in young versus middle-aged female rats.
Main Methods:
- Vascular responses to chronic relaxin versus placebo were quantified in isolated mesenteric arteries and kidneys of young (10-12 wk) and middle-aged (40-46 wk) Wistar Hannover rats.
- Techniques included pressure-perfusion myography, wire myography, and an isolated perfused rat kidney model.
- Relaxin family peptide receptor 1 (Rxfp1) gene expression was analyzed using quantitative polymerase chain reaction.
Main Results:
- In young rats, relaxin significantly enhanced nitric oxide (NO)-dependent vasodilation and reduced myogenic reactivity in mesenteric arteries.
- In aged rats, relaxin did not alter any measured mesenteric or renal vascular parameters.
- Aged rats exhibited lower renal perfusion flow compared to young rats, despite comparable NO availability, and Rxfp1 expression was similar across age groups.
Conclusions:
- Moderate aging blunts the physiological vasodilator response to relaxin, affecting both endothelium-dependent and -independent pathways.
- While endothelial function may remain normal, the vascular system's responsiveness to relaxin diminishes with age.
- These findings highlight age-related changes in vascular adaptation and suggest impaired relaxin signaling in aging.
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