The effects of finasteride (Proscar) on hair growth, hair cycle stage, and serum testosterone and dihydrotestosterone in adult male and female stumptail macaques (Macaca arctoides).
Finasteride, a 5 alpha-reductase inhibitor, was administered orally (1 mg/kg.day) for 6 months to six male and five female stumptail macaques. Vehicle was given to five male and five female animals over the same period of time. Hair weights in a defined 1-in.2 area of frontal scalp were measured periodically every 1-2 months, and serum was collected for measurement of testosterone and dihydrotestosterone. In addition, scalp biopsies were taken before and 6 months after treatment to evaluate the micromorphometry of hair follicles. Results showed that both male and female serum dihydrotestosterone levels were significantly reduced (60-70%) by finasteride treatment. Both males and females showed statistically significant increases in mean hair weight over the treatment period compared to controls (P = 0.034). In addition, there was a statistically significant increase in mean follicle length (measured histologically in scalp biopsies) compared to baseline in the finasteride-treated animals (P = 0.028). These data show that an inhibition of 5 alpha-reductase in the stumptail macaque can reverse the balding seen with age in both the male and female animals.
Merck Research Laboratories, Rahway, New Jersey 07065-0900.
L
L
Rhodes
J
J
Harper
H
H
Uno
G
G
Gaito
J
J
Audette-Arruda
S
S
Kurata
C
C
Berman
R
R
Primka
B
B
Pikounis
D000818:Animals; D013196:Dihydrotestosterone / Q000097:blood*; D005260:Female; D018120:Finasteride / Q000494:pharmacology*; D006197:Hair / Q000033:anatomy & histology / Q000187:drug effects* / Q000254:growth & development*; D008251:Macaca / Q000502:physiology*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D012016:Reference Values; D013739:Testosterone / Q000097:blood*
D013196:Dihydrotestosterone; D013739:Testosterone; D018120:Finasteride