title: Decreased intestinal CYP3A and P-glycoprotein activities in rats with adjuvant arthritis.
abstract: Adjuvant-induced arthritis (AA) rats have been used as an animal model for rheumatoid arthritis. Several studies have shown that the pharmacokinetics of a number of drugs are altered in AA rats. We investigated the effects of AA on the barrier functions of the intestine using a rat model. Intestinal CYP3A activities (midazolam 1'-hydroxylation and 7-benzyloxy-4-(trifluoromethyl)-coumarin 7-hydroxylation) in AA rats were significantly decreased compared with those in normal rats, with marked decrease observed in the upper segment of intestine. Intestinal P-glycoprotein (P-gp) activity at upper segment was also significantly decreased in AA rats to 60% of that in normal rats, and the other segments (middle and lower) of intestine also exhibited tendencies toward decrease in P-gp activity. This decrease was supported by the finding that levels of mdr1a mRNA and P-gp protein were decreased in AA rats. No significant differences were observed in intestinal paracellular and transcellular permeability between AA and normal rats. These results suggest that intestinal CYP3A and P-gp activities are decreased in AA rats, and that the pharmacokinetics and bioavailabilities of drugs whose membrane permeation is limited by intestinal CYP3A and/or P-gp may be altered in rheumatic diseases.
authors.affiliation: Department of Pharmacy, Kinki University, Osaka, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Uno
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kawase
authors.forename: Akiko
authors.initials: A
authors.lastname: Tsuji
authors.forename: Tadatoshi
authors.initials: T
authors.lastname: Tanino
authors.forename: Masahiro
authors.initials: M
authors.lastname: Iwaki
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000378:metabolism; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D018528:ATP-Binding Cassette Transporters / Q000378:metabolism; D000818:Animals; D000983:Antipyrine / Q000378:metabolism; D001169:Arthritis, Experimental / Q000378:metabolism*; D015153:Blotting, Western; D002851:Chromatography, High Pressure Liquid; D051544:Cytochrome P-450 CYP3A / Q000378:metabolism*; D015194:Diffusion Chambers, Culture; D005260:Female; D005456:Fluorescent Dyes; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000201:enzymology; D008861:Microsomes / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D008874:Midazolam / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011899:Ranitidine / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020112:Rhodamine 123