TY - JOUR
T1 - Feed-forward control of prostate growth
T2 - Dihydrotestosterone induces expression of its own biosynthetic enzyme, steroid 5α-reductase
AU - George, Fredrick W.
AU - Russell, David W.
AU - Wilson, Jean D.
PY - 1991
Y1 - 1991
N2 - Dihydrotestosterone, the primary mediator of prostate growth, is synthesized in target tissues from the circulating androgen testosterone through the action of steroid 5α-reductase (EC 1.3.99.5). The expression of 5α-reductase and the level of 5α-reductase messenger RNA in rat ventral prostate are regulated by androgens. To determine whether this control is mediated by dihydrotestosterone or testosterone, we investigated the effect of finasteride, a potent inhibitor of steroid 5α-reductase, on the expression of 5α-reductase in the prostate. The administration of finasteride to intact rats for 7 days caused a 55% decrease in prostate weight and an 87% decrease in 5α-reductase enzyme activity. Furthermore, the restoration of prostate growth after castration and the enhancement in 5α-reductase enzyme activity and 5α-reductase messenger RNA level by testosterone administration were blocked by finasteride, whereas the inhibitor had no effect on dihydrotestosterone-mediated increases in 5α-reductase activity or messenger RNAlevel. These findings indicate that dihydrotestosterone itself controls prostate growth and 5α-reductase activity. They further suggest that prostate growth is controlled by a feed-forward mechanism by which formation of trace amounts of dihydrotestosterone induces 5α-reductase, thereby increasing dihydrotestosterone synthesis and triggering a positive developmental cascade. (.
AB - Dihydrotestosterone, the primary mediator of prostate growth, is synthesized in target tissues from the circulating androgen testosterone through the action of steroid 5α-reductase (EC 1.3.99.5). The expression of 5α-reductase and the level of 5α-reductase messenger RNA in rat ventral prostate are regulated by androgens. To determine whether this control is mediated by dihydrotestosterone or testosterone, we investigated the effect of finasteride, a potent inhibitor of steroid 5α-reductase, on the expression of 5α-reductase in the prostate. The administration of finasteride to intact rats for 7 days caused a 55% decrease in prostate weight and an 87% decrease in 5α-reductase enzyme activity. Furthermore, the restoration of prostate growth after castration and the enhancement in 5α-reductase enzyme activity and 5α-reductase messenger RNA level by testosterone administration were blocked by finasteride, whereas the inhibitor had no effect on dihydrotestosterone-mediated increases in 5α-reductase activity or messenger RNAlevel. These findings indicate that dihydrotestosterone itself controls prostate growth and 5α-reductase activity. They further suggest that prostate growth is controlled by a feed-forward mechanism by which formation of trace amounts of dihydrotestosterone induces 5α-reductase, thereby increasing dihydrotestosterone synthesis and triggering a positive developmental cascade. (.
KW - 4-azasterold inhibitors
KW - Androgen action
KW - Testoterone metabolism
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U2 - 10.1073/pnas.88.18.8044
DO - 10.1073/pnas.88.18.8044
M3 - Article
C2 - 1654556
AN - SCOPUS:0025873322
SN - 0027-8424
VL - 88
SP - 8044
EP - 8047
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 18
ER -