Comparison of finasteride
(Proscar), a 5 alpha reductase inhibitor.
Study
TITLE
Comparison of finasteride (Proscar), a
5 alpha reductase inhibitor, and various commercial plant extracts in in vitro
and in vivo 5 alpha reductase inhibition.
AUTHOR
Rhodes L; Primka RL; Berman C; Vergult
G; Gabriel M; Pierre-Malice M; Gibelin B
ORGANISATION
Department of Biochemistry, Merck
Research Laboratories, Rahway, New Jersey 07065.
SOURCE
Prostate 1993; 22 (1): 43-51
LANGUAGE OF
PUBLICATION
English
ABSTRACT
Human prostate was used as a source of
5 alpha reductase. Compounds were incubated with an enzyme preparation and
[3H]testosterone. [3H]-dihydrotestosterone production was measured to calculate
5 alpha reductase activity. IC50 values (ng/ml) were finasteride=1;
Permixon=5,600; Talso=7,000; Strogen Forte=31,000; Prostagutt=40,000; and
Tadenan=63,000. Bazoton and Harzol had no activity at concentrations up to
500,000 ng/ml. In castrate rats stimulated with testosterone (T) or
dihydrotestosterone (DHT), finasteride, but not Permixon or Bazoton, inhibited T
stimulated prostate growth, while none of the three compounds inhibited DHT
stimulated growth. These results demonstrate that finasteride inhibits 5 alpha
reductase, while Permixon and Bazoton have neither anti-androgen nor 5 alpha
reductase inhibitory activity. In addition, in a 7 day human clinical trial,
finasteride, but not Permixon or placebo, decreased serum DHT in men, further
confirming the lack of 5 alpha reductase inhibition by Permixon. Finasteride and
the plant extracts listed above do not inhibit the binding of DHT to the rat
prostatic androgen receptor (concentrations to 100 micrograms/ml). Based on
these results, it is unlikely that these plant extracts would shrink the
prostate by inhibiting androgen action or 5 alpha reductase. (AUTHOR)
MJTR: Androstenes PD. Azasteroids PD.
Plant Extracts PD. Testosterone 5-alpha-Reductase AI.
MNTR: Animal. Comparative Study. Human.
In Vitro. Male. Prostate DE. Prostate EN. Rats. Receptors, Androgen DE.
Stanolone BL. Testosterone BL. CLINICAL TRIAL. CONTROLLED CLINICAL TRIAL.
JOURNAL ARTICLE
RNUM: EC 1.3.99.5 (Testosterone
5-alpha-Reductase); 0 (Androstenes); 0 (Azasteroids); 0 (Permixon); 0 (Plant
Extracts); 0 (Receptors, Androgen); 521-18-6 (Stanolone); 57-85-2
(Testosterone); 98319-26-7 (Finasteride)
GEOT: UNITED STATES
IDEN: ISSN: 0270-4137. JOURNAL-CODE:
PB4. ENTRY-DATE: 930226. JOURNAL-SUBSET: M X. IM-DATE: 9305.
ACCE: 93149919
