PHYSIOLOGICAL AND BIOCHEMICAL EFFECTS OF PREGNANCY IN UNINEPHRECTOMIZED RABBITS

A model of mild, persistent renal impairment was produced following uninephrectomy in 6 month old female New Zealand white rabbits infected with Encephalitozoon cuniculi. The effect of three consecutive pregnancies was assessed. No difference in plasma creatinine, creatinine clearance or total protein excretion was found at 15 months of age between 5 uninephrectomized pregnant rabbits and 5 uninephrectomized virgin animals. Mean plasma urea (11.6 +/- 0.4 mmol/1) was higher at 15 months of age in 5 uninephrectomized pregnant rabbits than in 5 uninephrectomized virgin animals (7.7 +/- 0.7 mmol/1)(p < 0.001). During pregnancy plasma urea fell in both uninephrectomized pregnant and control pregnant animals. Total urinary protein excretion increased from 0.04 +/- .01 gm/24hrs pre-pregnancy to 0.09 +/- .02 gm/24hrs during late pregnancy in uninephrectomized rabbits (p < 0.04). Mean arterial blood pressure in the 10 uninephrectomized animals increased from 81 +/- 3 mmHg to 92 +/- 3 mmHg at sacrifice (p = 0.022). Repetitive pregnancies do not appear to have a sustained adverse effect on kidney function in rabbits with mild functional renal impairment.