The Effect of Hypophysectomy upon Corticosterone-Induced Ovulation in the Hen (Gallus domesticus)

Abstract

When the ovary of a laying hen contains a mature follicle, ovulation can be induced by an injection of corticosterone. The dose which is required to consistently induce a premature ovulation causes the plasma concentration of corticosterone in the peripheral blood to rise to levels which are higher than those normally observed during the ovulation cycle. The accompanying rise and fall in progesterone which follows an injection of corticosterone. It was concluded that the pituitary gland for both ovulation and progesterone secretion to occur.

Effect of Photoperiod on the Concentrations of Corticosterone and Luteinizing Hormone in the Plasma of the Domestic Hen

“…This is not so, however, on the night of the first ovulation of a sequence when the preovulatory release of progesterone at the beginning of the open period is associated with a suppression of corticosterone secretion (Wilson & Cunningham, 1980a). Injection of hens with adrenocorticotrophic hormone or corticosterone when the ovary contains a follicle capable of being ovulated stimulates the release of LH (Sharp & Beuving, 1978;Wilson & Lacassagne, 1978) and progesterone (Etches & Simons, 1979) and induces ovulation (van Tienhoven, 1961;Soliman & Huston, 1974). It has, however, been suggested that the dose of corticosterone used in these experiments raises blood concentrations to a level greater than that normally found during the ovulatory cycle (Sharp & Beuving, 1978;Etches & Simons, 1979).…”

“…Injection of hens with adrenocorticotrophic hormone or corticosterone when the ovary contains a follicle capable of being ovulated stimulates the release of LH (Sharp & Beuving, 1978;Wilson & Lacassagne, 1978) and progesterone (Etches & Simons, 1979) and induces ovulation (van Tienhoven, 1961;Soliman & Huston, 1974). It has, however, been suggested that the dose of corticosterone used in these experiments raises blood concentrations to a level greater than that normally found during the ovulatory cycle (Sharp & Beuving, 1978;Etches & Simons, 1979). While this observation tends to discount a physiological role for corticosterone in the induction of ovulation in the hen there is some evidence of adrenal involvement in the timing of the hormonal events leading to ovulation.…”