Linked Life Data

11129951

Source:http://linkedlifedata.com/resource/pubmed/id/11129951

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2000-12-20
pubmed:abstractText
The catalytic requirements and the role of P450 3A9, a female-specific isoform of CYP3A from rat brain, in the metabolism of several steroid hormones were studied using recombinant P450 3A9 protein. The optimal steroid hormone hydroxylase activities of P450 3A9 required cholate but not cytochrome b5. P450 3A9 was active in the hydroxylation reactions of testosterone, androstenedione, progesterone and dehydroepiandrosterone (DHEA). No activity of P450 3A9 toward cortisol was detectable under our reconstitution conditions. Among all the steroid hormones examined, female-specific P450 3A9 seemed to catalyze most efficiently the metabolism of progesterone, one of the major female hormones, to form three mono-hydroxylated products, 6beta-, 16alpha-, and 21-hydroxyprogesterone. Our data also showed that P450 3A9 can catalyze the formation of a dihydroxy product, 4-pregnen-6beta, 21-diol-3, 20-dione, from progesterone with a turnover number, 1.3 nmol/min/nmol P450. Based on the Vmax/Km values for P450 3A9 using either 21-hydroxprogesterone or 6beta-hydroxyprogesterone as a substrate, 4-pregnen-6beta, 21-diol-3, 20-dione may be formed either by 6beta-hydroxylation of 21-hydroxprogesterone or 21-hydroxylation of 6beta-hydroxyprogesterone. As a major isoform of CYP3A expressed in rat brain, the activities of P450 3A9 toward two major neurosteroids, progesterone and DHEA suggested a possible role for P450 3A9 in the metabolism of neurosteroids.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0300-8177
pubmed:author
pubmed:issnType
Print
pubmed:volume
213
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
127-35
pubmed:dateRevised
2008-10-10
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Cytochrome P450 3A9 catalyzes the metabolism of progesterone and other steroid hormones.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, University of Texas Medical School, Houston 77225, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.