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Updated: Aug 7, 2026
06:55
Assessment of Maternal Vascular Remodeling During Pregnancy in the Mouse Uterus
Published on: December 5, 2015
Nitric oxide-mediated vasodilation in human pregnancy
D J Williams1, P J Vallance, G H Neild
1Department of Nephrology, University College London Medical School, United Kingdom.
The American Journal of Physiology
|February 1, 1997
Summary
Nitric oxide (NO) significantly contributes to blood vessel dilation in pregnant women. Increased NO generation during pregnancy helps lower peripheral vascular resistance, impacting maternal circulation.
Area of Science:
- Physiology
- Reproductive Biology
- Cardiovascular Science
Background:
- Maternal circulation undergoes significant vasodilation during pregnancy.
- The precise mechanisms, particularly the role of nitric oxide, require further elucidation.
Purpose of the Study:
- To investigate the contribution of nitric oxide to pregnancy-induced vasodilation.
- To assess the impact of nitric oxide synthase inhibition on maternal hand blood flow.
Main Methods:
- Venous occlusion plethysmography was used to measure hand blood flow.
- N(G)-monomethyl-L-arginine (L-NMMA), a nitric oxide synthase inhibitor, and norepinephrine were infused.
- Comparisons were made between nonpregnant, early pregnant, and late pregnant women.
Main Results:
- Basal hand blood flow was significantly higher in late pregnancy.
- L-NMMA caused a greater reduction in hand blood flow in pregnant groups, indicating increased nitric oxide activity.
- Norepinephrine's vasoconstrictive effect was attenuated in late pregnancy.
Conclusions:
- Increased nitric oxide generation is implicated in the reduction of peripheral vascular resistance during healthy human pregnancy.
- Findings suggest a crucial role for nitric oxide in mediating gestational vasodilation.
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