In-vitro studies of the effects of oestrogen pretreatment on the sensitivity of the immature female rat pituitary gland to stimulation with gonadotrophin releasing hormone

Details

Serval ID
serval:BIB_695EDE14F7FB
Type
Article: article from journal or magazin.
Collection
Publications
Title
In-vitro studies of the effects of oestrogen pretreatment on the sensitivity of the immature female rat pituitary gland to stimulation with gonadotrophin releasing hormone
Journal
Journal of Endocrinology
Author(s)
Wilkinson  M., De Ziegler  D., Cassard  D., Ruf  K. B.
ISSN
0022-0795
Publication state
Published
Issued date
07/1977
Peer-reviewed
Oui
Volume
74
Number
1
Pages
11-21
Notes
In Vitro
Journal Article --- Old month value: Jul
Abstract
The effects of oestrogen priming on the sensitivity of the anterior pituitary gland to stimulation with gonadotrophin releasing hormone (GnRH) was investigated in immature female rats using a new organ culture technique. Hemipituitary glands obtained from animals primed with a single dose of oestradiol benzoate (OB; 20 microgram/100 g body weight) released significantly more LH when pulsed with GnRH (4 nmol/1) than did control hemipituitary glands. This potentiating effect was detectable as early as 5 days after birth. After a second stimulation, LH secretion remained high. These results were compared with those obtained from animals treated to induce increased levels of endogenous oestrogen on day 26 of life. Thus, hemipituitary glands were obtained from animals given two injections of OB, an injection of pregnant mare serum gonadotrophin (PMSG) or a unilateral brain lesion placed in the basal hypothalamus. Pituitary tissue was stimulated as before with a pulse of GnRH. Two injections of OB enhanced the sensitivity to stimulation. Conversely, both PMSG and lesion treatment severely reduced the sensitivity to GnRH, although PMSG-treated and lesioned animals have been used as models for the study of ovulation.
Keywords
Animals Estradiol/*pharmacology Female Gonadotropin-Releasing Hormone/*pharmacology Gonadotropins, Equine/pharmacology Hypothalamus/injuries/physiology Luteinizing Hormone/secretion Pituitary Gland/*secretion Pituitary Gland, Anterior/drug effects/*secretion Rats Stimulation, Chemical
Pubmed
Web of science
Create date
28/02/2008 11:37
Last modification date
20/08/2019 14:24
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