Journal of Andrology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
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
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Tang, K.
Right arrow Articles by Yun, J. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tang, K.
Right arrow Articles by Yun, J. S.

Journal of Andrology, Vol 15, Issue 1 9-14, Copyright © 1994 by The American Society of Andrology

JOURNAL ARTICLE

Testosterone feedback on gonadotropin secretion and gene expression in transgenic mice expressing human growth hormone gene

K. Tang, A. Bartke, C. S. Gardiner, T. E. Wagner and J. S. Yun
Department of Physiology, School of Medicine, Southern Illinois University, Carbondale.

To determine the effects of testosterone on the regulation of gonadotropins in metallothionein-1/human growth hormone (MT/hGH) transgenic mice, basal and gonadotropin-releasing hormone (GnRH)-stimulated luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release from incubated pituitaries, as well as pituitary content of LH, FSH, and mRNA for their respective beta subunits, were measured in normal and transgenic males that were injected with testosterone propionate (5 micrograms/g body weight; 24 hours before autopsy), injected with oil vehicle, castrated for 10 days, or sham operated. In normal (non-transgenic) males, exogenous testosterone induced the expected suppression, and castration induced the expected stimulation of various parameters of gonadotropin synthesis and release. In contrast, in testosterone-treated and in castrated MT/hGH transgenic mice the release of LH and the pituitary levels of LH-beta mRNA did not differ from the corresponding values measured in vehicle-injected and sham-operated transgenic controls. Pituitary LH content was elevated in testosterone-treated MT/hGH transgenic mice but was not changed in castrated transgenic males. The changes in pituitary levels of FSH and FSH-beta mRNA and in FSH release in MT/hGH transgenic mice in response to testosterone and castration were different from the changes in LH and LH-beta mRNA in the same mice, but similar to the changes of FSH and FSH-beta message produced in normal mice by identical treatments. We suggest that hGH expression attenuates the effects of testosterone on the mechanisms controlling LH release, with less influence on testosterone regulation of LH synthesis. These effects of hGH expression appear to be selective for LH, without influencing the FSH control system.


This article has been cited by other articles:


Home page
 Exp. Biol. Med.Home page
A. Bartke, V. Chandrashekar, D. Turyn, R. W. Steger, L. Debeljuk, T. A. Winters, J. A. Mattison, N. A. Danilovich, W. Croson, D. R. Wernsing, et al.
Effects of Growth Hormone Overexpression and Growth Hormone Resistance on Neuroendocrine and Reproductive Functions in Transgenic and Knock-Out Mice
Experimental Biology and Medicine, November 1, 1999; 222(2): 113 - 123.
[Abstract] [Full Text]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1994 by The American Society of Andrology.