We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Immunoreactive Dynorphin Is Regulated by Estrogen in the Rat Anterior Pituitary.
- Authors
Fullerton, Meryl J.; Smith, A. Ian; Funder, John W.
- Abstract
The pituitary and hypothalamic content of dynorphin was determined by radioimmunoassay and characterized by high-performance liquid chromatography (HPLC) in adult female Sprague-Dawley rats, intact and ovariectomized with and without estrogen treatment. Animals were given estradiol benzoate, or vehicle (oil) by six daily intramuscular injections. Anterior pituitary content of immunoreactive (ir)-dynorphin in ovariectomized rats was approximately twice that of intact animals, and consisted of a single HPLC peak co-eluting with dynorphin 32. Administration of estradiol benzoate (0.06-6 μg/day) caused a marked decrease of ir-dynorphin in the anterior lobe of castrate female rats, with a half-maximal effect at 0.2 μg/day; levels were restored to those seen in intact animals with 6 μg estradiol benzoate per day, an effect which was not influenced by concomitant administration of progesterone (1 mg/day), or bromocriptine (100 μg/day). In the hypothalamus and neuro-intermediate lobe multiple peaks of immunoreactive dynorphin were seen, coeluting with dynorphin A 1-8, dynorphin A 1-17 and dynorphin 32. Neither castration nor estrogen treatment altered ir-dynorphin content in these tissues. These findings suggest that the ovary exerts a specific modulating influence on AP ir-dynorphin in the rat, and that in addition this inhibition appears to be mediated by ovarian estrogen. Copyright © 1988 S. Karger AG, Basel
- Publication
Neuroendocrinology, 1988, Vol 47, Issue 1, p1
- ISSN
0028-3835
- Publication type
Article
- DOI
10.1159/000124882