Increased uterine artery blood flow in hypoxic murine pregnancy is not sufficient to prevent fetal growth restriction.

Increased uterine artery blood flow in hypoxic murine pregnancy is not sufficient to prevent fetal growth restriction. Biol Reprod. 2019 Nov 11;: Authors: Lane SL, Doyle AS, Bales ES, Lorca RA, Julian CG, Moore LG Abstract Incomplete maternal vascular responses to pregnancy contribute to pregnancy complications including intrauterine growth restriction and preeclampsia. We aimed to characterize maternal vascular dysfunction in a murine model of fetal growth restriction as an approach toward identifying targetable pathways for improving pregnancy outcomes. We utilized a murine model of late-gestation hypoxia-induced intrauterine growth restriction that reduced E18.5 fetal weight by 34%. Contrary to our hypothesis, uterine artery blood flow as measured in vivo by Doppler ultrasound was increased in mice housed under hypobaric hypoxia (385 mmHg; 5500 m) vs normoxia (760 mmHg, 0 m). Using wire myography, uterine arteries isolated from hypoxic mice had similar vasodilator responses to the two activators A769662 and acetylcholine as those from normoxic mice, although the contribution of an increase in nitric oxide production to uterine artery vasodilation was reduced in the hypoxic vs. normoxic groups. Vasoconstrictor responses to phenylephrine and potassium chloride were unaltered by hypoxia. The levels of activated AMPK were reduced with hypoxia in both the uterine artery and placenta as measured by western blot and immunohistochemis...
Source: Biology of Reproduction - Category: Reproduction Medicine Authors: Tags: Biol Reprod Source Type: research