Acute changes in serum gonadotrophins and steroids following orchidectomy in the rat: role of the adrenal gland.
Orchidectomy in male rats leads to a) an increase in serum LH and FSH within 9 h; b) a decrease in serum testosterone to baseline levels by 30 min; c) an increase in serum progesterone (for 30 to 120 min), in the presence of the adrenals. If adrenalectomy is performed simultaneously with orchidectomy, the LH and FSH rises at 9 and 12 h are abolished, and the rises at 24 h are attenuated or abolished. By 48 h, the orchidectomized-adrenalectomized rat has achieved a rise in serum LH and FSH equal to that found in gonadectomy alone. Two hypotheses are offered to explain the abolition of the early gonadotrophin rises after combined orchidectomy-adrenalectomy treatment: a) the early responses are due to increased serum progesterone, on a background of decreased testosterone; b) the early responses are abolished because of the missing corticosterone, which either forces competition between pituitary secretion of ACTH and LH/FSH, or is necessary for rapid gonadotroph-secretory response. The differences and similarities between male and female rats, in the response of LH and FSH to gonadectomy, in the presence  or absence of the adrenals, are discussed.
D000311:Adrenal Glands / Q000502:physiology*; D000315:Adrenalectomy; D000818:Animals; D002369:Castration; D005019:Ethyl Ethers / Q000494:pharmacology; D005640:Follicle Stimulating Hormone / Q000097:blood*; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D011374:Progesterone / Q000097:blood*; D051381:Rats; D013739:Testosterone / Q000097:blood*; D013997:Time Factors
D005019:Ethyl Ethers; D013739:Testosterone; D011374:Progesterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone