These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Cytochrome P450 3A expression and function in liver and intestinal mucosa from dexamethasone-treated sheep.
    Author: Maté ML, Lifschitz A, Sallovitz J, Ballent M, Muscher AS, Wilkens MR, Schröder B, Lanusse C, Virkel G.
    Journal: J Vet Pharmacol Ther; 2012 Aug; 35(4):319-28. PubMed ID: 21906085.
    Abstract:
    The effects of repeated administrations of dexamethasone (DEX) (3 mg/kg/day by i.m. route for 7 days) on the gene expression profile of a cytochrome P450 (CYP) 3A28-like isoenzyme, on the expression of a CYP3A-immunoreactive protein and on CYP3A-dependent metabolic activities in sheep liver and small intestinal mucosa were evaluated in the current work. CYP 3A-dependent metabolic activities (erythromycin and triacetyl-oleandomycin N-demethylations) were assessed in microsomal fractions. The mRNA expression of CYP3A28-like, glucocorticoid receptor, constitutive androstane receptor, pregnane X receptor and retinoic X receptor alpha (RXRα) was determined by quantitative real-time PCR. The expression of a CYP3A-immunoreactive protein was measured by Western blot analyses. In the liver, DEX treatment increased CYP3A28-like mRNA levels (2.67-fold, P<0.01) and CYP3A apoprotein expression (1.34-fold, P<0.05) and stimulated CYP3A-dependent metabolism. High and significant correlation coefficients between CYP3A-dependent activities and CYP3A28-like gene (r=0.835-0.856, P<0.01) or protein (r=0.728-0.855, P<0.05) expression profiles were observed. Among the transcriptional factors, DEX only stimulated (2.1-fold, P<0.01) the mRNA expression of RXRα. In sheep small intestine, DEX caused a slight increment (34.6%, P<0.05) in erythromycin N-demethylase activity in the jejunal mucosa and a significant enhancement (P<0.05) of CYP3A apoprotein level in the duodenal mucosa.
    [Abstract] [Full Text] [Related] [New Search]