title: Gene and protein expression of P-glycoprotein, MRP1, MRP2, and CYP3A4 in the small and large human intestine.
abstract: The cytochrome P450 3A4 enzyme and the ABC-transporters may affect the first-pass extraction and bioavailability of drugs and metabolites. Conflicting reports can be found in the literature on the expression levels of efflux transporters in human intestine and how they vary along the intestine. The relative levels of mRNA and protein of CYP3A4 and the ABC tranporters Pgp (ABCB1), MRP1 (ABCC1), and MRP2 (ABCC2) were determined using RT-PCR and Western blot for human intestinal tissues (n = 14) from jejunum, ileum and colon. The expression of mRNA for CYP3A4, Pgp, and MRP2 was highest in jejunum and decreased toward more distal regions, whereas MRP1 was equally distributed in all intestinal regions. For CYP3A4, a more significant correlation could be established between mRNA and protein expression than for the ABC transporters. The samples showed considerable interindividual variability, especially at the protein level. The apically located Pgp and MRP2 showed a similar expression pattern along the human intestine as for CYP3A4. The gene expression of MRP1 exhibited a more uniform distribution.
authors.affiliation: Department of Pharmacy, Uppsala University, Uppsala, Sweden.
authors.forename: Sofia
authors.initials: S
authors.lastname: Berggren
authors.forename: Christine
authors.initials: C
authors.lastname: Gall
authors.forename: Nadine
authors.initials: N
authors.lastname: Wollnitz
authors.forename: Mats
authors.initials: M
authors.lastname: Ekelund
authors.forename: Urban
authors.initials: U
authors.lastname: Karlbom
authors.forename: Janet
authors.initials: J
authors.lastname: Hoogstraate
authors.forename: Dieter
authors.initials: D
authors.lastname: Schrenk
authors.forename: Hans
authors.initials: H
authors.lastname: Lennernäs
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D051544:Cytochrome P-450 CYP3A; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D006801:Humans; D007420:Intestine, Large / Q000378:metabolism*; D007421:Intestine, Small / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism*; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D051544:Cytochrome P-450 CYP3A; D003577:Cytochrome P-450 Enzyme System; D026901:Membrane Transport Proteins; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D012333:RNA, Messenger; C000715087:ABCC2 protein, human; C510163:CYP3A4 protein, human; C421109:multidrug resistance-associated protein 1