Article

Tissue distribution and hormonal regulation of the breast cancer resistance protein (Bcrp/Abcg2) in rats and mice.

Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160-7417, USA.
Biochemical and Biophysical Research Communications (impact factor: 2.48). 02/2005; 326(1):181-7. DOI:10.1016/j.bbrc.2004.11.012 pp.181-7
Source: PubMed

ABSTRACT Breast cancer resistance protein (Bcrp/Abcg2) is a member of the ABC transporter family. The purpose of this study was to quantify Bcrp mRNA in rat and mouse tissues, and to determine whether there are gender differences in Bcrp mRNA expression. Rat Bcrp mRNA levels were high in intestine and male kidney, and intermediate in testes. Mouse Bcrp expression was highest in kidney, followed by liver, ileum, and testes. Male-predominant expression of Bcrp was observed in rat kidney and mouse liver. Furthermore, gonadectomy and hypophysectomy experiments were conducted to determine whether sex steroids and/or growth hormone are responsible for Bcrp gender-divergent expression patterns. Male-predominant expression of Bcrp in rat kidney appears to be due to the suppressive effect of estradiol, and male-predominant expression of Bcrp in mouse liver appears to be due to the inductive effect of testosterone.

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Keywords

ABC transporter family
 
Bcrp gender-divergent expression patterns
 
Bcrp mRNA
 
Bcrp mRNA expression
 
Bcrp/Abcg2
 
Breast cancer resistance protein
 
gonadectomy
 
growth hormone
 
hypophysectomy experiments
 
inductive effect
 
intestine
 
male kidney
 
male-predominant expression
 
Mouse Bcrp expression
 
mouse liver
 
mouse tissues
 
Rat Bcrp mRNA levels
 
rat kidney
 
suppressive effect
 
testes