Estrogen effects on plasma volume, arterial blood pressure, interstitial space, plasma proteins, and blood viscosity in sheep.
In adult castrated ewes the infusion of 17 beta-estradiol for 3 weeks was associated with a 12% increase in body weight, a 20% increase in whole blood volume (mainly due to a 27% increase of plasma volume), a 13% decrease in mean arterial blood pressure, and a 40% increase in heart rate. The change in plasma volume correlated with the change in estradiol concentration (r = 0.72). Most of the fluid was retained in the interstitial space, as represented by a 6 kg weight gain, 10% of which was in the intravascular compartment. Whole blood and plasma viscosity increased 16% and 21%, respectively, thus reversing some of the blood volume effects toward a hyperdynamic cardiovascular state. We conclude that many of the cardiovascular and hematologic changes with estrogen administration are similar to the changes observed during pregnancy, with the proposed requirement of decrease in mean arterial blood pressure as a condition for blood volume expansion.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D001798:Blood Proteins / Q000032:analysis*; D004958:Estradiol / Q000097:blood / Q000494:pharmacology* / Q000502:physiology; D004970:Estrone / Q000097:blood; D005110:Extracellular Space / Q000187:drug effects*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D010953:Plasma Volume / Q000187:drug effects*; D012756:Sheep
D001798:Blood Proteins; D004970:Estrone; D004958:Estradiol