Back to Search Start Over

Prolactin inhibits annexin 5 expression and apoptosis in the corpus luteum of pseudopregnant rats: involvement of local gonadotropin-releasing hormone.

Authors :
Kawaminami M
Shibata Y
Yaji A
Kurusu S
Hashimoto I
Source :
Endocrinology [Endocrinology] 2003 Aug; Vol. 144 (8), pp. 3625-31.
Publication Year :
2003

Abstract

We investigated a specific relationship between the expression of annexin 5 and prolactin in the corpus luteum of pseudopregnant rats, with particular interest in GnRH and apoptosis of luteal cells. The expression of ovarian annexin 5 mRNA was significantly decreased at mid-pseudopregnancy and recovered at the end, whereas it remained low on the corresponding day of pregnancy. The dopamine agonist CB-154, administered at mid-pseudopregnancy (d 5), increased ovarian annexin 5 mRNA, whereas prolactin, given daily for 3 d to cycling rats, decreased it. An immunocytochemical study also showed that annexin 5 increased in the corpus luteum on d 6 and 7 of pseudopregnancy after treatment with CB-154 on d 5. The distribution of annexin 5-positive cells was not uniform in the corpus luteum and matched that of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL)-positive cells. Because GnRH stimulates annexin 5 mRNA expression in the gonadotropes, involvement of the GnRH receptor was examined. Local administration of a GnRH antagonist, Cetrorelix, to hemilateral ovarian bursa of pseudopregnant rats simultaneously receiving CB-154 abrogated both the expression of annexin 5 and the TUNEL reaction. The present results clearly demonstrate that prolactin decreases annexin 5 mRNA in the luteal cells during pseudopregnancy. Prolactin is suggested to suppress the local action of GnRH, which stimulates annexin 5 synthesis and apoptosis of functional luteal cells during pseudopregnancy.

Details

Language :
English
ISSN :
0013-7227
Volume :
144
Issue :
8
Database :
MEDLINE
Journal :
Endocrinology
Publication Type :
Academic Journal
Accession number :
12865345
Full Text :
https://doi.org/10.1210/en.2003-0118