Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Ontogeny of sex differences in LH and FSH levels 48 h after castration in the rat

Ontogeny of sex differences in LH and FSH levels 48 h after castration in the rat DIVERSE PITUITARY luteinizing hormone (LH) secretory responses to removal of testes and ovaries in rats are an enigmatic feature of the control of gonadotropin secretion (5). Removal of the testes in an adult male results in increased serum LH levels within 9 h (23); yet, removal of the ovaries in a metestrous female does not seem to trigger pituitary release of LH for at least 48 h (3). Various hypotheses have been proposed to explain this divergence. One of the most popular is known as the “most recent steroid seen” hypothesis and suggests that the rate of increase in serum LH after removal of negative feedback restraints on the hypothalamic-pituitary axis is due to the steroid last seen by this axis. That is, removal of estrogen regardless of genetic sex would result in a delayed LH rise as typically seen in the ovariectomized female, and removal of testosterone, again regardless of genetic sex, would result in an immediate increase in THE E460 serum levels of LH. This hypothesis was originally tested by Gay and Hauger (14), who found that removal of testosterone capsules from ovariectomized rats resulted in minor increases in serum LH similar to increases seen after http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png AJP - Endocrinology and Metabolism The American Physiological Society

Ontogeny of sex differences in LH and FSH levels 48 h after castration in the rat

Download PDF
5 pages

Loading next page...
 
/lp/the-american-physiological-society/ontogeny-of-sex-differences-in-lh-and-fsh-levels-48-h-after-castration-zfjlcZMAil

References

References for this paper are not available at this time. We will be adding them shortly, thank you for your patience.

Publisher
The American Physiological Society
Copyright
Copyright © 1981 the American Physiological Society
ISSN
0193-1849
eISSN
1522-1555
Publisher site
See Article on Publisher Site

Abstract

DIVERSE PITUITARY luteinizing hormone (LH) secretory responses to removal of testes and ovaries in rats are an enigmatic feature of the control of gonadotropin secretion (5). Removal of the testes in an adult male results in increased serum LH levels within 9 h (23); yet, removal of the ovaries in a metestrous female does not seem to trigger pituitary release of LH for at least 48 h (3). Various hypotheses have been proposed to explain this divergence. One of the most popular is known as the “most recent steroid seen” hypothesis and suggests that the rate of increase in serum LH after removal of negative feedback restraints on the hypothalamic-pituitary axis is due to the steroid last seen by this axis. That is, removal of estrogen regardless of genetic sex would result in a delayed LH rise as typically seen in the ovariectomized female, and removal of testosterone, again regardless of genetic sex, would result in an immediate increase in THE E460 serum levels of LH. This hypothesis was originally tested by Gay and Hauger (14), who found that removal of testosterone capsules from ovariectomized rats resulted in minor increases in serum LH similar to increases seen after

Journal

AJP - Endocrinology and Metabolism – The American Physiological Society

Published: Dec 1, 1981

There are no references for this article.