help button home button Endocrine Society Endocrinology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text (PDF)
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Day, R.
Right arrow Articles by Akil, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Day, R.
Right arrow Articles by Akil, H.

Endocrinology, Vol 133, 2652-2659, Copyright © 1993 by Endocrine Society

ARTICLES

Prodynorphin gene expression in the rat intermediate pituitary lobe: gender differences and postpartum regulation

R Day, MK Schafer, MW Collard, E Weihe and H Akil
J. A. DeSeve Laboratory of Biochemical Neuroendocrinology, Clinical Research Institute of Montreal, Quebec, Canada.

The distribution of prodynorphin (proDyn) messenger RNA (mRNA) was examined in the rat pituitary using Northern and in situ hybridization analysis. Anterior pituitary gonadotrophs are known to express ProDyn, but the present study demonstrated that proDyn mRNA was also expressed in the intermediate lobe melanotrophs and was colocalized with POMC mRNA. The 2.6-kilobase proDyn transcript observed in the intermediate lobe was shown to be translatable by polysome analysis. Immunohistochemical studies showed dynorphin (Dyn)-like immunoreactivity in all intermediate lobe melanotrophs. Intermediate lobe proDyn gene expression was not regulated by dopamine, in contrast to intermediate lobe POMC mRNA levels, which were increased with haloperidol and decreased with bromocriptine treatment, as expected. A gender difference in ProDyn gene expression was noted, since intermediate lobes of male rats had nearly 2-fold higher proDyn mRNA levels than intermediate lobes of female rats. In contrast, no gender difference of intermediate lobe POMC mRNA levels were detected. ProDyn mRNA levels were up-regulated by 3- to 4-fold in the intermediate lobes of postpartum females as compared to pregnant or nonpregnant female rats, whereas POMC mRNA levels were unchanged, suggesting a role for intermediate lobe ProDyn in the postpartum period of the female rat. Although our results demonstrate proDyn and POMC coexpression in the pituitary intermediate lobe melanotrophs and show a differential regulational control for each gene in this tissue, the present data also strengthen the notion that proDyn is a precursor that has a role to play in reproductive functions.


This article has been cited by other articles:


Home page
 Endocr. Rev.Home page
N. Ben-Jonathan and R. Hnasko
Dopamine as a Prolactin (PRL) Inhibitor
Endocr. Rev., December 1, 2001; 22(6): 724 - 763.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
R. Day, C. Lazure, A. Basak, A. Boudreault, P. Limperis, W. Dong, and I. Lindberg
Prodynorphin Processing by Proprotein Convertase 2. CLEAVAGE AT SINGLE BASIC RESIDUES AND ENHANCED PROCESSING IN THE PRESENCE OF CARBOXYPEPTIDASE ACTIVITY
J. Biol. Chem., January 9, 1998; 273(2): 829 - 836.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Endocrinology Endocrine Reviews J. Clin. End. & Metab.
Molecular Endocrinology Recent Prog. Horm. Res. All Endocrine Journals
Copyright © 1993 by The Endocrine Society