PubMed · 7515760
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
D E Neal. 1994. Transurethral prostatectomy.. https://doi.org/10.1002/bjs.1800810403
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Androgens play a key role in human fetal development. Therefore, it is important to understand the distribution of the isozymes of 5 alpha-reductase, the enzyme that converts testosterone to the more potent androgen, dihydrotestosterone. The expression of the two isozymes of 5 alpha-reductase was studied in human fetal skin and fetal prostate by measuring the in vitro enzyme activity in crude preparations. Low levels of the type 1 5 alpha-reductase were found in fetal scalp and back skin. Studies with fetal prostate samples confirmed that the type 2 enzyme is expressed in levels similar to those found in adult tissues. These results provide the first evidence that both isozymes of 5 alpha-reductase are expressed during human fetal development.
Inhibitors of 5 alpha-reductase may be effective in the treatment of 5 alpha-dihydrotestosterone-dependent abnormalities, such as benign prostate hyperplasia, prostate cancer and certain skin diseases. The green tea catechins, (-)epigallocatechin-3-gallate and (-)epicatechin-3-gallate, but not (-)epicatechin and (-)epigallocatechin, are potent inhibitors of type 1 but not type 2 5 alpha-reductase. (-)Epigallocatechin-3-gallate also inhibits accessory sex gland growth in the rat. These results suggest that certain tea gallates can regulate androgen action in target organs.
Elevated dihydrotestosterone levels have been suggested to increase the risk of prostate cancer. The human SRD5A2 gene encodes the type II steroid 5 alpha-reductase, which converts testosterone to the more bioactive compound dihydrotestosterone. We have determined the distribution of a dinucleotide repeat in low-risk Asian-Americans, high-risk African-Americans, and intermediate-risk non-Hispanic Whites. We found this marker to be more polymorphic than previously reported, with some alleles being specific to African-Americans. Genetic variants of the SRD5A2 gene may play a role in predisposition to prostate cancer and in explaining the substantial racial/ethnic variability in risk.