TRANSIENT ALTERATION OF THE REPRODUCTIVE FUNCTION IN NEPHROTIC RATS

The reproductive function of male and female rats with induced nephrot ic syndrome was examined by assessing hormonal levels, the estrous cyc le pattern and fertility. Measurements were carried out on day 10 (nep hrotic stage) and on day 30 (remission stage) after treatment (a singl e s.c. dose of puromycin aminonucleoside 15 mg/ 100 g body wt.). Serum concentrations of luteinizing hormone (LH), follicle-stimulating horm one (FSH) and progesterone (P-4) from both sexes as well as 17 beta-es tradiol (E-2) in females and total testosterone (tT) in males were ass ayed at both phases of the illness by specific radioimmunoassays; free and urine testosterone (fT, uT) was also determined in male rats on d ay 10. The estrous cycle was followed alongside the study through vagi nal smears, while fertility was estimated by the rate of pregnancies ( females) or pregnancy induction (males), and by the litter size. The r esults showed that most serum hormone levels, except FSH in females, w ere significantly reduced at the nephrotic stage of the illness, retur ning to their normal values after 30 days. Besides, on day 10, fT was found reduced in nephrotic males, while uT concentrations remained unm odified. The ovulatory cycle of nephrotic rats was disrupted on day 3 and not restored until day 23; nevertheless, the reproductive function , measured as a fertility index, was fully reinstalled at the remissio n stage. interestingly, the capacity of fertilization of the nephrotic males was not entirely abolished during the acute phase, since 37 % o f the animals were fertile. Moreover, on day 30 the reproductive funct ion in nephrotic males was totally recovered. The data from this study show the existence of reversible endocrine disorders in rats bearing nephrotic syndrome; such changes are manifested during the acute phase of the illness as a temporary cessation of the reproductive processes .