Catecholamine-Mediated Diuresis in Turkeys 1

Abstract

Abstract

A catecholamine-mediated mechanism that may operate in water homeostasis of turkeys is described. Administration of epinephrine to turkeys in dosages that had few, or no, pressor or chronotropic effects (<4.0 μg. kg body wt^-1) stimulated urine flow. Increases in GFR and an unchanged urine to plasma inulin ratio were temporally related to the diuresis. These data suggest that epinephrine increases the number of functioning reptilian-type nephrons. Since this population of nephrons has little capacity for concentrating the glomerular filtrate the number of nephrons that are functional at a given time is important for water balance. Epinephrine, norepinephrine, and dopamine produced diuresis, but epinephrine was most potent.