title: Interaction of propafenone enantiomers with human alpha 1-acid glycoprotein.
abstract: The interaction of propafenone enantiomers with human alpha 1-acid glycoprotein was studied using high-performance liquid chromatography. Each of the two optical antipodes interacted with one class of high-affinity binding sites characterized by Ka(R) = (6.18 +/- 0.93) x 10(5) M-1, n(R) = 1.34 +/- 0.09 for the (R)-isomer and Ka(S) = (8.93 +/- 1.82) x 10(5) M-1, n(S) = 0.99 +/- 0.08 for the (S)-isomer. Nonspecific binding to secondary low-affinity high-capacity binding site(s) was only slightly greater in the case of the (S)-enantiomer (n'k'(S) = (1.06 +/- 0.09) x 10(4) M-1) compared to the (R)-enantiomer (n'k'(R) = (6.87 +/- 0.72) x 10(3) M-1). It was concluded that both enantiomers interact with common single class of high-affinity binding sites on AAG (along with nonspecific binding) exhibiting only slight stereoselectivity for propafenone.
authors.affiliation: Institute of Experimental Pharmacology, Slovak Academy of Sciences, Bratislava, Czechoslovakia.
authors.forename: J
authors.initials: J
authors.lastname: Oravcová
authors.forename: W
authors.initials: W
authors.lastname: Lindner
authors.forename: P
authors.initials: P
authors.lastname: Szalay
authors.forename: L
authors.initials: L
authors.lastname: Bohácik
authors.forename: T
authors.initials: T
authors.lastname: Trnovec
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007700:Kinetics; D015394:Molecular Structure; D009961:Orosomucoid / Q000378:metabolism*; D011405:Propafenone / Q000097:blood* / Q000737:chemistry; D011485:Protein Binding; D013237:Stereoisomerism
chemical_list: D009961:Orosomucoid; D011405:Propafenone