Plasma volume in fasted pregnant rats

The pattern of plasma volume changes in well-nourished and in food- or protein-restricted pregnant rats

Plasma volume and plasma protein were measured on days 5, 12, 19, and 21 of gestation in rats fed 25% casein either ad libitum or 55% food restricted, or fed 6% casein ad libitum (protein restricted). Both forms of undernutrition prevented the large increase in plasma volume observed in well-fed rats by day 19. The pattern of plasma volume change, with maximum mean values on day 19 (compared to the other measurement days), was not altered by undernutrition. Differences in plasma protein concentration or total circulating protein did not explain plasma volume changes.