• Media type: E-Article
  • Title: Renal and Hormonal Effects of Water Deprivation in Late-Term Pregnant Rats
  • Contributor: Salas, Sofía P.; Giacaman, Andrea; Vío, Carlos P.
  • Published: Ovid Technologies (Wolters Kluwer Health), 2004
  • Published in: Hypertension, 44 (2004) 3, Seite 334-339
  • Language: English
  • DOI: 10.1161/01.hyp.0000138405.94275.a2
  • ISSN: 0194-911X; 1524-4563
  • Origination:
  • Footnote:
  • Description: Water-retaining hormones are stimulated during pregnancy allowing normal volume expansion. Because pregnant rats actively retain water, we postulate that water deprivation (WD) would cause a greater reduction in plasma volume in pregnant than in nonpregnant rats. To test this hypothesis, Sprague-Dawley pregnant and nonpregnant rats were water-deprived for 48 hours. At day 19 of pregnancy, or in the corresponding day in nonpregnant rats, they were randomly assigned to either a WD or a control (C) pair-fed group (n=10 to 12 per group). WD significantly reduced body weight, food intake, and creatinine clearance, and increased urinary osmolality in nonpregnant and pregnant rats. WD reduced plasma volume in a similar proportion in nonpregnant and pregnant rats (nonpregnant rats C=13.1±0.4, WD=11.0±0.2; pregnant rats C=19.4±0.7, WD=16.8±0.5 mL, P <0.001). Both groups of pregnant rats had a similar reduction in blood pressure. Plasma renin activity (nonpregnant rats C=6.1±1.1, WD=20.5±2.0; pregnant rats C=49±9.7, WD=94±12 ng angiotensin I/mL per hour, P <0.001) and plasma aldosterone levels were increased by pregnancy and further increased by WD. WD significantly reduced urinary kallikrein. WD caused a significant reduction in fetal but not placental weights. Present data indicate that 48-hour WD reduced renal kallikrein and further stimulated water-retaining hormones. We speculate that these are compensatory changes contributing to the maintenance of pregnancy in response to WD.
  • Access State: Open Access