Submit a comment
Citation Information: J Clin Invest. 1980;66(3):612-615. https://doi.org/10.1172/JCI109895.
Abstract
In vivo androgen kinetics were determined in six young (21--49 yr) and elderly men (62-77 yr) with prostatge hyperplasia (BPH). Steady-state infusions of [14C]testosterone and [3H]androstanediol (3 alpha diol) were given, which allowed determination of the conversions testosterone leads to dihydrotesterone (DHT) in equilibrium or formed from 3 alpha diol. These infusions also yield metabolic clearance data which, together with meaurement of nonisotopic steroid levels, yield estimations of blood production rates. The production rate for testosterone was 6.04 +/- 1.66 vs. 3.69 +/- 0.62 mg/d, whereas the production rate for 3 alpha diol was 319 +/- 57 and 193 +/- 34 micrograms/d (P < 0.05 both groups). The irreversible conversion rate of testosterone to DHT was 3.1 +/- 0.4 and 3.5 +/- 0.9% (NS). The back conversion of 3 alpha diol to dHT was high (68 +/- 25 vs. 81 +/- 17, NS) indicating that 3 alpha diol might cause BPH as a result of conversion to DHT in vivo. The conversion of DHT to 3 alpha diol is reduced in the elderly group (15.8 +/- 2.6 and 6.3 +/- 1.4, P < 0.001). Since DHT formation in the prostate is a key event in the development of BPH and blood DHT appears to be a measure of extrasplanchnic sexual target tissue activity, our in vivo studies suggest that the tissue increase in DHT may result from reduced metabolism and the activity of 3 alpha-oxidoreduction favors the oxidative pathway in elderly men.
Authors
I Morimoto, A Edmiston, R Horton
Guidelines
The Editorial Board will only consider comments that are deemed relevant and of interest to readers. The Journal will not post data that have not been subjected to peer review; or a comment that is essentially a reiteration of another comment.
- Comments appear on the Journal’s website and are linked from the original article’s web page.
- Authors are notified by email if their comments are posted.
- The Journal reserves the right to edit comments for length and clarity.
- No appeals will be considered.
- Comments are not indexed in PubMed.
Specific requirements
- Maximum length, 400 words
- Entered as plain text or HTML
- Author’s name and email address, to be posted with the comment
- Declaration of all potential conflicts of interest (even if these are not ultimately posted); see the Journal’s conflict-of-interest policy
- Comments may not include figures
Copyright © 2023 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)