Effects of postnatal corticosterone treatment on reproductive development in the rat

Abstract

Reproductive development was studied in rats in which corticosterone (25 mg/100 g body wt) mixed with an equal amount of cholesterol was implanted i.p. at Days 3, 6, 12 or 18 after birth. Vaginal perforation in rats treated on Days 12 or 18 was advanced by 10 days but reproductive function in the treated animals was generally disrupted. A variable incidence of persistent vaginal oestrus was observed in adult females given implants on Days 3 and 6, and of prolonged vaginal dioestrus in those treated on Days 12 or 18. All treated females had lordosis quotients lower than those of untreated controls, the effect being most pronounced at the earlier ages of treatment. The results are believed to indicate two periods in reproductive development which are differentially affected by corticosterone.

Neonatal glucocorticoid administration: effect on the diurnal rhythm of serum concentrations of corticosterone, progesterone and LH, and the response to pregnant mare serum gonadotrophin in immature female rats

“…Two possible mechan¬ isms would appear to warrant further study. The first is that cortisol acetate may delay development of centres which respond to the positive feedback actions of oestrogen on LH secretion as has been suggested by others (Turner & Taylor, 1977). This may have led, in the present study, to a reduced serum progesterone response to PMSG, and a lower number of cortisol acetate-treated rats ovulating by day 28.…”

“…Neonatal injections of glucocorticoids can also alter reproductive maturation of female rats (Cost & Mann, 1976;Turner & Taylor, 1977). Female rats given corticosterone implants on postnatal days 3 or 6 exhibited persistent vaginal oestrus as adults, while animals given implants of the steroid on days 12 or 18 exhibited prolonged periods of dioestrus (Turner & Taylor, 1977).…”

“…Female rats given corticosterone implants on postnatal days 3 or 6 exhibited persistent vaginal oestrus as adults, while animals given implants of the steroid on days 12 or 18 exhibited prolonged periods of dioestrus (Turner & Taylor, 1977). Turner & Taylor (1977) proposed that increased levels of corticosterone during perinatal life may alter differentiation of those brain centres involved in feedback regulation of gonadotrophin secretion, but this hypothesis has not been tested.…”

“…Female rats given corticosterone implants on postnatal days 3 or 6 exhibited persistent vaginal oestrus as adults, while animals given implants of the steroid on days 12 or 18 exhibited prolonged periods of dioestrus (Turner & Taylor, 1977). Turner & Taylor (1977) proposed that increased levels of corticosterone during perinatal life may alter differentiation of those brain centres involved in feedback regulation of gonadotrophin secretion, but this hypothesis has not been tested. A single injection of cortisol or dexamethasone to female rats on postnatal day 3 delayed vaginal opening and increased the length of oestrous cycles, but the critical period for luteinizing hormone (LH) release was not altered in adults (Cost & Mann, 1976).…”

The Effects of Neonatal Hydrocortisone on Rat Cerebellar Development

“…Neural development is re tarded by this treatment as indicated by the delayed maturation of sensory evoked poten tials, the swimming response, the startle reflex and ability to exhibit a tonic-clonic seizure [38,40,46]. Rodents treated neonatally with glucocorticoids also differ as adults in emo tionality, locomotor activity, motor coor dina tion and sexual responsiveness [19,32,45].…”