IPSIndian Journal of Pharmacology
Home  IPS  Feedback Subscribe Top cited articles Login 
Users Online : 9740 
Small font sizeDefault font sizeIncrease font size
Navigate Here
 »   Next article
 »   Previous article
 »   Table of Contents

Resource Links
 »   Similar in PUBMED
 »  Search Pubmed for
 »  Search in Google Scholar for
 »Related articles
 »   Citation Manager
 »   Access Statistics
 »   Reader Comments
 »   Email Alert *
 »   Add to My List *
 * Requires registration (Free)

 Article Access Statistics
    PDF Downloaded173    
    Comments [Add]    

Recommend this journal


Year : 1999  |  Volume : 31  |  Issue : 2  |  Page : 120-123

Effects of finasteride and epristeride on steroid 5a-reductase kinetics-A comparative in vitro study

Correspondence Address:
Zu-Yue Sun

Login to access the Email id

Source of Support: None, Conflict of Interest: None

Rights and PermissionsRights and Permissions

Objective: To compare the effect of finasteride with that of epristeride on 5(-reductase kinetics in vitro to explain the increase in serum testosterone level by finasteride but not by epristeride when treated for benign prostatic hyperplasia. Methods: Sprague-Dawley rat liver microsomal crude suspension served as the source of steroid ?(?-reductase. The enzyme, Tris-HCl buffer, [3H] testosterone and epristeride or finasteride were incubated together at 37oC for 20 min. The substrate, [3H] testosterone, and its product, [3H] dihydrotestosterone (DHT) were isolated by thin-layer chromatography. To measure the initial velocity of [3H] DHT (the activity of 5(-reductase), the radioactivity of [3H] DHT, scrapped off thin-layer plate was determined with isotope scintillation counter. The enzyme activity was expressed as (M/min of [3H] DHT. Results: Epristeride was an uncompetitive inhibitor, but finasteride was a competitive one to steroid 5(- reductase and their inhibition constants were 67 ( 19 and 25 ( 3 nM, respectively. Conclusion: The inhibition mechanism of finasteride different from epristeride perhaps was the reason for increase in serum testosterone levels in patients with benign prostatic hyperplasia treated by finasteride.


Print this article     Email this article

Site Map | Home | Contact Us | Feedback | Copyright and Disclaimer | Privacy Notice
Online since 20th July '04
Published by Wolters Kluwer - Medknow