Reference : Hormones modulate the concentration of cytoplasmic progestin receptors in the brain o...
Scientific journals : Article
Human health sciences : Endocrinology, metabolism & nutrition
Life sciences : Zoology
Social & behavioral sciences, psychology : Neurosciences & behavior
Hormones modulate the concentration of cytoplasmic progestin receptors in the brain of male ring doves (Streptopelia risoria).
Balthazart, Jacques mailto [> > > >]
Blaustein, J. D. [> > > >]
Cheng, M. F. [> > > >]
Feder, H. H. [ > > ]
Journal of Endocrinology
Society for Endocrinology
Yes (verified by ORBi)
United Kingdom
[en] Animals ; Binding, Competitive ; Brain/drug effects/metabolism ; Castration ; Columbidae/metabolism ; Cytoplasm/metabolism ; Dihydrotestosterone/pharmacology ; Gonadal Steroid Hormones/pharmacology ; Male ; Progestins ; Promegestone/metabolism ; Receptors, Progesterone/drug effects/metabolism
[en] A cytoplasmic progestin receptor has been characterized in the brain of castrated ring doves using an in-vitro assay that measures the binding of a synthetic progestin, [3H]17 alpha,21-dimethyl-19-nor-pregna-4,9-diene-3,20-dione(promegestone; R5020). The affinity of the receptor was similar in both the hyperstriatum and the hypothalamus (Kd approximately equal to 4 X 10(-10) mol/l). Its concentration was higher in the anterior hypothalamus-preoptic area (63 +/- 4 fmol/mg (S.E.M.) protein) than in other brain regions (posterior hypothalamus, 33 +/- 5; hyperstriatum, 28 +/- 3; midbrain, 17 +/- 4 fmol/mg protein; n = 7). Progesterone and R5020 competed well for binding but oestradiol and 5 beta-dihydrotestosterone did not. Corticosterone and, to a lesser extent, testosterone and 5 alpha-dihydrotestosterone completed for binding but much higher concentrations were required than for progestins. Injections of testosterone (200 micrograms testosterone propionate daily for 7 days) significantly increased the concentration of progestin receptors in the anterior and posterior hypothalamus without having any significant effect on other brain areas. Shorter treatment, lasting for 2 days, with testosterone propionate (200 micrograms daily), 5 alpha-dihydrotestosterone (200 micrograms daily) or oestradiol benzoate (50 micrograms daily) did not always cause this increase but seven injections of oestradiol benzoate (50 micrograms daily for 7 days) were even more effective than seven injections of testosterone propionate (200 micrograms daily for 7 days). These data suggested that the sensitivity to progesterone of the brain of the bird changes as a consequence of increases in the level of testosterone in the circulation.

There is no file associated with this reference.

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.