Urinary Excretion of Epinephrine and Norepinephrine During Fasting in Late Pregnancy in the Rat

Abstract

Twenty-four hr urinary excretions of catecholamines did not differ in pregnant, post partum and age-matched virgin rats when they were given unrestricted access to food. Significant differences became manifest when food was withheld: Fasting from day 19–21 of gestation elicited significant increases in urinary epinephrine on each of the 2 days and increased urinary norepinephrine on the second. Contrariwise, urinary catecholamines were not increased when the same animals were fasted again on day 10–12 post partum or when agematched virgin rats were subjected to comparable dietary deprivation. It has been suggested that the differences during fasting between gravid and nongravid rats may be ascribed to the greater homeostatic challenge that is posed by starvation in late pregnancy, and by the hypoglycemia that may occur under these circumstances. The potential contributions of enhanced sympathoadrenal activity to the metabolic response to starvation during gestation have been discussed. (Endocrinology84: 447, 1969)