Mechanism of Natriuretic Effect of Oxytocin

摘要

In rats, intramuscular injection of oxytocin (0.25 nmol/100 g body weight) increased sodium excretion from 19 +/- 5 to 120 +/- 11 mu mol/min. A significant correlation (p<0.001) was revealed between renal excretion of oxytocin and sodium ions. Under the action of oxytocin, natriuresis was characterized by diminished reabsorption of fluid in the proximal tubule of the nephron attested by elevated lithium clearance rate and from stimulation of V-1a receptors in the cells of thick ascending loop of Henle. Pmp-Tyr(Me)-Phe-Gln-Asn-Cys-Pro-Arg-Gly-NH2, a V-1a receptors antagonist, prevented the natriuretic effect of oxytocin.