title: Effect of dose of metoprolol on its elimination by isolated perfused rat liver in vitro.
abstract: The effects of dose of metoprolol (Met) on hepatic elimination was studied in isolated rat liver perfused at a flow of 25 ml.min-1. The results showed that Met was eliminated by rat liver in accordance with one-compartment model. Linear kinetic eliminating processes (apparent first-order kinetics) were found in doses of Met 0.2, 0.5, 1.0, and 2.0 mg, T1/2 were 8.3, 8.8, 9.6, and 10.6 min and the clearance rate were 11.7, 11.8, 9.6, and 8.6 ml.min-1, respectively. Nonlinear eliminating processes were found in doses of Met 4, 8, and 12 mg. Vm and Km were 0.98, 1.05, and 0.94 microgram/min-1.ml-1 and 15.6, 16.9, and 14.6 micrograms.ml-1, respectively. It is concluded that hepatic Met elimination is independent on lower doses, but rested upon high doses.
authors.affiliation: Department of Pharmacology, Nanjing Medical College, China.
authors.forename: G S
authors.initials: GS
authors.lastname: Shen
authors.forename: Y D
authors.initials: YD
authors.lastname: Zhang
authors.forename: M Y
authors.initials: MY
authors.lastname: Li
authors.forename: J P
authors.initials: JP
authors.lastname: Shen
authors.forename: Y
authors.initials: Y
authors.lastname: Ding
authors.forename: D K
authors.initials: DK
authors.lastname: Huang
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism*; D008297:Male; D008790:Metoprolol / Q000008:administration & dosage / Q000493:pharmacokinetics*; D010477:Perfusion; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D008790:Metoprolol