Pitocin Restoration of Renal Hemodynamics to Pre-Neurohypophysectomy Levels

Abstract

Glomerular filtration rate (GFR), renal plasma flow (RPF) and tubular maxima were strikingly and predictably reduced by a neurohypophysectomy procedure in the dog which did not produce obvious adenohypo-physial dysfunction. Renal hemodynamics in such preparations were effectively restored to preoperative levels by administration of the total extract of the neurohypophysis (Pituitrin) as well as by its oxytocic fraction (Pitocin). The pressor fraction (Pitressin) of the total extract had no effect on GFR, RPF or tubular maxima in the neurohypophysectomized preparations observed. The foregoing results are compatible with the interpretation that the lowered renal activity is due to an extirpation deficiency in the oxytocic neurophypophysial principle and that restoration of renal hemodynamics by Pitocin to the pre-extirpation level constitutes direct replacement therapy.