The effects of growth hormone (GH) on two constitutively expressed rat liver cytochrome P-450 (P-450) enzymes, namely P-450f (IIC7) and P-450PB1 (IIC6), have been investigated. Hypophysectomy of both male and female rats results in low expression of P-450f. Single daily injections of GH cannot restore expression of P-450f but further repress it. Continuous administration of GH, on the other hand, increases expression of P-450f to levels comparable to those of the normal male and female rat. P-450PB1 is minimally affected by hypophysectomy or GH treatment, although a weak but significant repression by continuous administration of GH can be detected. Run-on analysis shows that continuous GH treatment increases transcription of P-450f. In addition, the sequence of the 5′ flanking region of this gene reveals DNA segments that might have a putative role in the transcriptional regulation of P-450f by GH.
|Original language||English (US)|
|Number of pages||6|
|State||Published - Jan 1 1990|
ASJC Scopus subject areas
- Molecular Medicine