help button home button Endocrine Society Endocrinology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
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 Chen, T. T.
Right arrow Articles by Frawley, L. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chen, T. T.
Right arrow Articles by Frawley, L. S.

Endocrinology, Vol 125, 1904-1909, Copyright © 1989 by Endocrine Society

ARTICLES

Relative importance of newly synthesized and stored hormone to basal secretion by growth hormone and prolactin cells

TT Chen, RD Kineman, JG Betts, JB Hill and LS Frawley
Department of Anatomy and Cell Biology, Medical University of South Carolina, Charleston 29425.

It is generally accepted that under basal conditions there is preferential release of newly synthesized hormone by a number of endocrine cell type, including those that secrete GH or PRL. However, the cellular basis for this phenomenon along with the relative contribution of stored hormone to basal secretion has yet to be clearly established. In the present study, we employed reverse hemolytic plaque assays to monitor basal and stimulated release of GH and PRL from individual cells in which de novo protein synthesis had been blocked. Monodispersed pituitaries from adult male rats were cultured for 21 h in the absence or presence of maximally effective doses of puromycin (100 microM) or cycloheximide (36 microM) and were then subjected to separate plaque assays for GH or PRL. Treatment with puromycin reduced the percentage of GH or PRL secretors (plaque formers) by about half. Coincubation with stimulatory secretagogues did not increase the percentages of GH or PRL secretors in control cultures, but returned the proportion in puromycin-treated cells to normal, demonstrating that cells which failed to secrete basally could still release hormone from their stored pools when stimulated. Very similar results were obtained when these experiments were repeated with cycloheximide. Taken together, these results demonstrate that only a fraction of the cells that release GH or PRL are dependent upon newly synthesized hormone for basal secretion; the remainder appear capable of mobilizing stored hormone for this purpose even in the absence of stimulation.


This article has been cited by other articles:


Home page
 J. Cell Sci.Home page
R. A. Bauer, R. L. Overlease, J. L. Lieber, and J. K. Angleson
Retention and stimulus-dependent recycling of dense core vesicle content in neuroendocrine cells
J. Cell Sci., May 1, 2004; 117(11): 2193 - 2202.
[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 © 1989 by The Endocrine Society