The Effects of Dietary Ascorbic Acid Treatment on Mesenteric Artery Reactivity in Pregnant Rats with Reduced Uterine Perfusion Pressure

Abstract

Preeclampsia is a multifaceted disease of pregnancy mediated by poor placental perfusion. The symptoms of the disease include hypertension, hyperuricemia, and proteinuria. Pregnant rats with reduced uteroplacental perfusion (RUPP) have been used as an animal model of preeclampsia. In these animals plasma ascorbate levels are decreased along with increased vascular reactivity similar to what is seen in patients with preeclampsia. Therefore, the aim of this study was to determine the effects of dietary ascorbic acid (AA) treatment to animals with RUPP and to see if detrimental changes in mesenteric vascular reactivity seen in RUPP rats can be ameliorated. Sprague Dawley rats were subjected to RUPP or Sham surgery on Day 14 of gestation. Animals were then given regular water or ascorbic acid water (1 mg/mL) ad libitum post surgery. At gestational Day 21, resistance‐sized mesenteric arteries were harvested and mounted in a pressurized arteriograph. Myogenic reactivity was significantly decreased in AA treated RUPP animals compared to RUPP (p<0.05). AA also reversed RUPP induced decreases in methacholine relaxation seen in RUPP (p<0.05). These results suggest that antioxidant treatment can partially reverse the increased myogenic reactivity and decreased endothelium‐dependent relaxation seen in animals with reductions in uterine perfusion and may provide new insights into the treatment of human preeclampsia.