title: Effects of 4-hydroxyantipyrine and its 4-O-sulfate on antipyrine as biodistribution promoter.
abstract: The effects of 4-hydroxyantipyrine (4-OH), a major metabolite of antipyrine, and its 4-O-sulfate (4-S) on the pharmacokinetics of antipyrine were investigated in rats. Plasma elimination of intravenously administered antipyrine was significantly decelerated under a steady-state concentration of 4-OH but not under that of 4-S. Tissue-to-plasma concentration ratio (Kp) of antipyrine under its steady-state concentration was significantly increased in the brain and heart by the concomitant use of 4-OH, while similar use of 4-S had no effect. The enhancement of the blood-brain barrier (BBB) permeability of antipyrine caused by the concomitant use of 4-OH was believed to be concerned with the increase of the Kp value of antipyrine in the brain. These results suggested that 4-OH could be used as a biodistribution promoter.
authors.affiliation: Faculty of Pharmaceutical Sciences, Okayama University, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Ohkawa
authors.forename: M
authors.initials: M
authors.lastname: Matsumura
authors.forename: Y
authors.initials: Y
authors.lastname: Kurosaki
authors.forename: M
authors.initials: M
authors.lastname: Kurumi
authors.forename: K
authors.initials: K
authors.lastname: Sasaki
authors.forename: T
authors.initials: T
authors.lastname: Nakayama
mesh_terms: D000818:Animals; D000983:Antipyrine / Q000493:pharmacokinetics*; D001812:Blood-Brain Barrier; D008297:Male; D011485:Protein Binding; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution
chemical_list: D000983:Antipyrine