Objective: The purpose of this study was to determine the influence of reduced uteroplacental perfusion pressure on plasma leptin and placental leptin receptor expression in rats that develop hypertension in the third trimester of pregnancy.
Study design: The ovarian arteries and abdominal aortae of pregnant Sprague-Dawley rats (n=9) were constricted surgically on day 14 of gestation and were matched with sham controls. Systolic blood pressure and weight were measured biweekly. Maternal plasma leptin levels, placental leptin receptor abundance, fetal number, fetal weight, and placental weight were determined.
Results: Reductions in perfusion pressure induced a significant decrease in maternal plasma leptin. Maternal systolic blood pressure and leptin receptor protein abundance was increased in the experimental group. Litter size and fetal and placental weight were significantly decreased in response to reduced perfusion pressure.
Conclusion: Reduced uteroplacental perfusion pressure reduces litter size, fetal and placental weights, and maternal plasma leptin levels and increases placental expression of leptin receptors.