Anterior pituitary sensitivity in immature female rats stimulated with gonadotrophin releasing hormone in vivo: effect of priming with oestrogen, pregnant mare serum gonadotrophin or brain lesion
Details
Serval ID
serval:BIB_4C534F4AFD9F
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Anterior pituitary sensitivity in immature female rats stimulated with gonadotrophin releasing hormone in vivo: effect of priming with oestrogen, pregnant mare serum gonadotrophin or brain lesion
Journal
Journal of Endocrinology
ISSN
0022-0795
Publication state
Published
Issued date
07/1977
Peer-reviewed
Oui
Volume
74
Number
1
Pages
99-109
Notes
Journal Article --- Old month value: Jul
Keywords
Animals
Estradiol/*pharmacology
Female
Follicle Stimulating Hormone/blood
Gonadotropin-Releasing Hormone/*pharmacology
Gonadotropins, Equine/*pharmacology
Hypothalamus/injuries
Luteinizing Hormone/blood
Pituitary Gland/*drug effects
Pituitary Gland, Anterior/*drug effects/physiology
Rats
Stimulation, Chemical
Time Factors
plasma luteinizing hormone (LH) and follicle stimulating hormone (FSH)
concentrations to stimulation with 1 or 2 injections of gonadotrophin
releasing hormone (GnRH) was investigated in 26-day-old immature female
rats which had received 1 of the following priming treatments: 1) 10 mcg
estradiol benzoate (EB) as a single injection on Day 23 or Day 25 or on
both days, 2) 10 IU pregnant mare serum gonadotrophin (PMSG) on Day 24, 3)
an electrochemical brain lesion placed in the mediobasal hypothalamus on
Day 23, or 4) control animals received either vehicle alone or a sham
lesion. Pituitary sensitivity assessed at 1000 hours on Day 26 after 1 or
2 injections of GnRH was enhanced to a similar degree in the 3 groups
treated with EB in terms of LH (p .01). FSH increased somewhat after EB
treatment. In contrast, 48 hours after the injection of PMSG pituitary
sensitivity, in terms of both LH and FSH, dropped sharply (p .001).
Sensitivity to 1 injection of GnRH was unchanged in lesioned rats.
However, a 2nd GnRH injection administered after an hour interval induced
a slightly larger LH response in control animals. In another study, rats
treated with EB on Day 23 and with 1 mg progesterone at 1200 hours on Day
26, pituitary sensitivity increased at both 1400 and 1700 hours as
compared with that in the Day 23 EB-treated group at 1000 hours.
PMSG-treated rats maintained their state of decreased responsiveness at
1400 hours, but exhibited increased sensitivity at the time of the
gonadotropin surge (1700 hours).
Pubmed
Web of science
Create date
28/02/2008 11:37
Last modification date
20/08/2019 14:00
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