Steroid 5alpha-reductase in cultured human fibroblasts. Biochemical and genetic evidence for two distinct enzyme activities.

Abstract

Various properties of the steroid 5alpha-reductase have been examined in cell-free extracts of skin and of fibroblasts cultured from genital and nongenital skin from control subjects and from patients with several forms of male pseudohermaphroditism. When 20alpha-hydroxy-4-[1,2-3H] pregnen-3-one was used as substrate, two 5alpha-reductase activities could be demonstrated in intact skin and cultured fibroblasts. The major activity, previously described for microsomes from human prepuce and extracts of cultured foreskin fibroblasts, is characterized by a narrow pH optimum near 5.5 and is limited to fibroblasts derived from genital skin. A second activity, not limited by the site of biopsy, has been demonstrated over a higher and broader range of pH (from 7 to 9); this enzyme activity is found in both genital and nongenital skin and in fibroblasts cultured from all skin regions. Whereas there is wide variability in the activity at pH 5.5 in genital skin fibroblasts, the activity at pH 7 to 9 is similar in fibroblasts derived from all anatomical sites. The two activities exhibit different kinetics with respect to steroid substrate and are also dissimilar in their subcellular distributions. Other properties, such as coenzyme requirement, steroid substrate specificity, and instability with increasing temperature, appear to be similar.

Statistics

0102030'96'98'00'02'04'06'08'10'12'14'16
Citations per Year

121 Citations

Semantic Scholar estimates that this publication has 121 citations based on the available data.

See our FAQ for additional information.

Cite this paper

@article{Moore1976Steroid5I, title={Steroid 5alpha-reductase in cultured human fibroblasts. Biochemical and genetic evidence for two distinct enzyme activities.}, author={Ronald J. Moore and Jean Wilson}, journal={The Journal of biological chemistry}, year={1976}, volume={251 19}, pages={5895-900} }