Elevation of Blood Pressure During Pregnancy in Uninephrectomized and Salt-Loaded Wistar Rats

Objective: The influence of uninephrectomy and salt loading on blood pressure (BP) during pregnancy was examined in pregnant Wistar rats.Methods: BP was measured by the indirect tail-cuff method every day during pregnancy in the following five groups: group 1 (n = 18, uninephrectomy on the first day of gestation + 8% high-salt diet), group 2 (n = 8, uninephrectomy + 0.4% low-salt diet), group 3 (n = 14, sham operation + high-salt diet), group 4 (n = 8, sham operation + low-salt diet), and group 5 (n = 8, nonpregnant female rats, uninephrectomy + high-salt diet).Results: Systolic BP in Group 1 increased significantly from midpregnancy and exceeded 140 mm Hg in late pregnancy. On day 17 of gestation, systolic BP in Group 1 (140.5 ± 4.3 mm Hg) was significantly higher than in the other four groups (114.8 ± 3.8, 123.1 ± 3.6, 117.9 ± 3.8, 123.0 ± 3.5 mm Hg, P < 0.05, respectively). Systolic BP was increased in uninephrectomized and salt-loaded pregnant rats but not in rats with two kidneys, uninephrectomized r...