title: Time-dependent effects of Klebsiella pneumoniae endotoxin (KPLPS) on the pharmacokinetics of theophylline in rats: return of the parameters in 96-hour KPLPS rats to the control levels.
abstract: It has been reported that theophylline is primarily metabolized via hepatic CYP1A1/2, 2B1/2, and 3A1/2, and 1,3-dimethyluric acid (1,3-DMU) is primarily formed via CYP1A1/2 in rats. Compared with control rats, the expression of CYP1A subfamily, 2B1/2, and 3A subfamily significantly decreased 24 h (24-h KPLPS rats) after intravenous administration of lipopolysaccharide derived from Klebsiella pneumoniae (KPLPS) to rats but returned to that in control rats after 96 h (96-h KPLPS rats). After intravenous or oral administration of theophylline to 24-h KPLPS rats, the values for the total area under the plasma concentration-time curve from time zero to time infinity of theophylline and 1,3-DMU became significantly greater (46.5 and 34.0% increase after intravenous and oral administration, respectively) and smaller (36.3 and 21.6% decrease, respectively), respectively. Because theophylline is a low hepatic extraction ratio drug in rats, the above results could have been due to significantly slower CL(int) for the disappearance of theophylline and for the formation of 1,3-DMU (37.1 and 60.6% decrease, respectively). However, in 96-h KPLPS rats, the pharmacokinetic parameters of theophylline and 1,3-DMU returned fully or partially to those in control rats. These findings indicate the existence of time-dependent effects of KPLPS on the pharmacokinetics of theophylline and 1,3-DMU in rats.
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, San 56-1, Shinlim-Dong, Kwanak-Gu, Seoul 151-742, South Korea.
authors.forename: Kyung H
authors.initials: KH
authors.lastname: Yang
authors.forename: Young S
authors.initials: YS
authors.lastname: Jung
authors.forename: Dae Y
authors.initials: DY
authors.lastname: Lee
authors.forename: Joo H
authors.initials: JH
authors.lastname: Lee
authors.forename: Young C
authors.initials: YC
authors.lastname: Kim
authors.forename: Myung G
authors.initials: MG
authors.lastname: Lee
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D007262:Infusions, Intravenous; D007711:Klebsiella pneumoniae; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013806:Theophylline / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D014527:Uric Acid / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D001993:Bronchodilator Agents; D008070:Lipopolysaccharides; D014527:Uric Acid; D003577:Cytochrome P-450 Enzyme System; D013806:Theophylline; C031274:1,3-dimethyluric acid