Linked Life Data

9569017

Source:http://linkedlifedata.com/resource/pubmed/id/9569017

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1998-5-13
pubmed:abstractText
Steroid hydroxylase cytochrome P450c17 has been previously purified from microsomal fractions of immature rat livers. In this study, we investigated the expression of P450c17 in rat livers to understand a role of steroidogenesis in the extrasteroidogenic tissue. Upon immunoblot analysis utilizing liver microsomes from rats, P450c17 was detected in 1 and 3 week old rats but not in adult rats. Data from immunohistochemical studies also showed a similar age-dependent expression of P450c17 and indicated that P450c17 detected in immature rat livers is localized in cells surrounding interlobular veins. This age-dependent expression of P450c17 in rat livers was observed in both sexes. Upon enzymatic analysis utilizing microsomal fractions from livers, levels of 17alpha-hydroxylase and 17,20-lyase activity for pregnenolone and progesterone increased by 3 weeks and dramatically reduced at 7 weeks, which is consistent with the expression level of P450c17. These data clearly indicate that P450c17 is expressed in immature rat liver to produce 17alpha-hydroxysteroids and C19-steroids. Based upon immunoblot analysis, the expression level of P450c17 in immature rat livers was approximately one third of that in testis. Compared expression level of P450c17 and total volume of organs between liver and testis, the total amount of steroid metabolites produced by liver P450c17 could be greater than that produced by gonadal P450c17. Because of the absence of P450c17 in rat adrenal glands, rat liver could be the major site for producing 17alpha-hydroxysteroids and C19-steroids in this particular period of life. Although physiological products formed by P450c17 in liver and their roles remain to be elucidated, this study suggests a large capacity of prepubertal rat liver for participating the production of steroid hormones and a putative importance of 17alpha-hydroxysteroids and C19-steroids, such as cortisol and androstendione, which are generally believed to be minor components of steroid hormones in rodents.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0960-0760
pubmed:author
pubmed:issnType
Print
pubmed:volume
64
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
121-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Evidence that immature rat liver is capable of participating in steroidogenesis by expressing 17alpha-hydroxylase/17,20-lyase P450c17.
pubmed:affiliation
Division of Natural Science, Osaka Kyoiku University, Kashiwara, Japan. katagiri@cc.osaka-kyoiku.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't