Format

Send to

Choose Destination
See comment in PubMed Commons below
J Clin Endocrinol Metab. 2011 Apr;96(4):1175-81. doi: 10.1210/jc.2010-2518. Epub 2011 Feb 2.

The effect of gonadotropin withdrawal and stimulation with human chorionic gonadotropin on intratesticular androstenedione and DHEA in normal men.

Author information

1
Departments of Internal Medicine, University of Washington, Seattle, Washington 91895, USA. mylang@u.washington.edu

Abstract

INTRODUCTION:

Concentrations of intratesticular (IT) testosterone (T) are known to be 100-200 times those of serum T; however, the IT concentrations of T's precursors, their testicular to serum gradients, gonadotropin dependence, and response to stimulation with human chorionic gonadotropin (hCG) have not been studied in detail. We hypothesized that serum and IT androstenedione (ADD) and IT dehydroepiandrosterone (DHEA) would be significantly suppressed by the administration of a GnRH antagonist and increased when stimulated by hCG, without a similar suppression of serum DHEA.

METHODS:

We suppressed gonadotropins in 23 normal men with the GnRH antagonist acyline and randomly assigned them to one of four doses of hCG, 0, 15, 60, or 125 IU sc every other day for 10 d. Blood and IT fluid for the measurement of serum and IT hormones were obtained at baseline and after 10 d of treatment.

RESULTS:

Baseline IT ADD [median (25th, 75th percentile)] was 629 (308, 860) nmol/liter, and IT DHEA was 564 (411, 879) nmol/liter, which were 175 and 27 times higher than their respective serum concentrations. IT ADD and IT DHEA were suppressed by 98 and 82%, respectively, by acyline and significantly increased with hCG administration. Likewise, serum ADD was suppressed by 50%, but serum DHEA was unchanged.

DISCUSSION:

ADD and DHEA are highly concentrated within the human testes compared with serum. Serum and IT ADD and IT DHEA are markedly suppressed with GnRH administration and stimulated by hCG, but serum DHEA is not, suggesting that most circulating DHEA is not of testicular origin.

PMID:
21289266
PMCID:
PMC3070251
DOI:
10.1210/jc.2010-2518
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Silverchair Information Systems Icon for PubMed Central
    Loading ...
    Support Center