title: Blood concentrations of acrylonitrile in humans after oral administration extrapolated from in vivo rat pharmacokinetics, in vitro human metabolism, and physiologically based pharmacokinetic modeling.
abstract: The present study defined a simplified physiologically based pharmacokinetic (PBPK) model for acrylonitrile in humans based on in vitro metabolic parameters determined using relevant liver microsomes, coefficients derived in silico, physiological parameters derived from the literature, and a prior previously developed PBPK model in rats. The model basically consists of a chemical absorption compartment, a metabolizing compartment, and a central compartment for acrylonitrile. Evaluation of a previous rat model was performed by comparisons with experimental pharmacokinetic values from blood and urine obtained from rats in vivo after oral treatment with acrylonitrile (30 mg/kg, a no-observed-adverse-effect level) for 14 days. Elimination rates of acrylonitrile in vitro were established using data from rat liver microsomes and from pooled human liver microsomes. Acrylonitrile was expected to be absorbed and cleared rapidly from the body in silico, as was the case for rats confirmed experimentally in vivo with repeated low-dose treatments. These results indicate that the simplified PBPK model for acrylonitrile is useful for a forward dosimetry approach in humans. This model may also be useful for simulating blood concentrations of other related compounds resulting from exposure to low chemical doses.
authors.affiliation: Laboratory of Drug Metabolism and Pharmacokinetics, Showa Pharmaceutical University, Machida, Tokyo, Japan.
authors.forename: Ryohji
authors.initials: R
authors.lastname: Takano
authors.forename: Norie
authors.initials: N
authors.lastname: Murayama
authors.forename: Kana
authors.initials: K
authors.lastname: Horiuchi
authors.forename: Masato
authors.initials: M
authors.lastname: Kitajima
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Kumamoto
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Shono
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamazaki
mesh_terms: D000181:Acrylonitrile / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000284:Administration, Oral; D000818:Animals; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D008954:Models, Biological; D019055:No-Observed-Adverse-Effect Level; D051381:Rats; D013045:Species Specificity
chemical_list: D000181:Acrylonitrile