TY  - JOUR
PY  - 1998//
TI  - Aromatization of 19-oxygenated androst-4-ene-3,6,17-triones with human placental microsomes
JO  - Biological and pharmaceutical bulletin
A1  - Numazawa, M.
A1  - Sugiyama, T.
A1  - Nagaoka, M.
SP  - 289
EP  - 292
VL  - 21
IS  - 3
N2  - To gain insight into the aromatization sequence of androst-4-ene-3,6,17-trione (1), a suicide substrate of aromatase, the aromatization of its 19-hydroxy and 19-oxo analogs 2 and 3 with human placental microsomes, was studied using GC-MS. Steroids 2 and 3 were separately incubated with the microsomes in the presence of NADPH in air. The GC-MS analysis of the trimethylsilyl derivative of the aromatization product indicated that both the 19-oxygenated steroids 2 and 3 were aromatized to yield 6-oxoestrogens, 6-oxoestrone (4) and 6-oxoestradiol (5), in each experiment. The aromatization rates of substrates 2 and 3 were 605+/-48 and 1794+/-75 pmol/mg protein/10 min, respectively. These relatively higher rates, compared to that of the parent steroid 1 (73.2+/-6.6 pmol/mg protein/10 min), indicates that the suicide substrate 1 is aromatized through the 19-oxygenated intermediates 2 and 3.<p /> <p>Language: en</p>
LA  - en
SN  - 0918-6158
UR  - http://dx.doi.org/10.1248/bpb.21.289
ID  - ref1
ER  -