Effect of arginine vasopressin and parathyroid hormone-related protein on renal function in the ovine foetus.

Abstract

1. The effects of intravenous infusions of arginine vasopressin (AVP), parathyroid hormone-related protein (PTHrP) and AVP+PTHrP on renal function in intact ovine foetuses at 100-125 days of gestation were examined. 2. A low dose of AVP (5.5 +/- 0.9 pmol/h) increased plasma AVP concentrations from 0.6 pmol/L to 2.1 +/- 0.4 pmol/L (mean +/- s.e.m; n = 8). This dose caused a significant reduction in free water clearance (CH2O; P < 0.001), without any significant change in fetal arterial blood pressure, glomerular filtration rate (GFR), or the urinary excretion rates of sodium, calcium or 3',5'-cyclic adenosine monophosphate (cAMP). 3. Infusions of PTHrP (1 nmol/h), with or without 1 nmol bolus..