title: A new antimicrobial quinolone (AM-1155) analysed in hair as an index of drug exposure and as a time-marker.
abstract: Scalp hair samples were obtained at one-month intervals for up to four months after the administration from each of twelve healthy male volunteers participating in a phase I study of a new antimicrobial quinolone, AM-1155, (+/-)-1-cyclopropyl-6-fluoro-1, 4-dihydro-8-methoxy-7-(cis-3,5-dimethyl-1-piperazinyl)-4-oxo-3-quinoline carboxylic acid. After hair was sectioned into 1 cm lengths from the scalp end, corresponding portions from five pieces of hair were dissolved in 1 M NaOH and assessed for AM-1155 by HPLC. In all subjects who had taken a single dose (600 mg, n = 6) or repeated doses (300 mg twice daily for 6.5 days, n = 6), the drug was detected in hair. The hair portions containing the drug were shown in most subjects to move outwards month by month at the rate of about 1 cm month-1. A single hair, which was obtained from each subject of the repeated-dose study 3 months after the completion of administration, was cut into 2.5-mm lengths from the scalp side and analysed for AM-1155. The drug was shown to be contained in 4 to 6 consecutive 2.5-mm lengths, showing that there was no large axial diffusion of the drug along the hair shaft even after 3 months. These findings indicate the utility of measuring this quinolone derivative in hair as an index of drug exposure and, furthermore, as a time marker for analysing other drugs in hair.
authors.affiliation: Department of Pharmacology, Hamamatsu University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Uematsu
authors.forename: H
authors.initials: H
authors.lastname: Kusajima
authors.forename: K
authors.initials: K
authors.lastname: Umemura
authors.forename: R
authors.initials: R
authors.lastname: Ishida
authors.forename: H
authors.initials: H
authors.lastname: Ohkubo
authors.forename: M
authors.initials: M
authors.lastname: Nakashima
mesh_terms: D000328:Adult; D000890:Anti-Infective Agents / Q000032:analysis*; D015415:Biomarkers; D002851:Chromatography, High Pressure Liquid; D024841:Fluoroquinolones; D000077734:Gatifloxacin; D006197:Hair / Q000737:chemistry* / Q000254:growth & development; D006801:Humans; D008297:Male; D010879:Piperazines / Q000032:analysis*; D015363:Quinolones / Q000032:analysis*; D013050:Spectrometry, Fluorescence
chemical_list: D000890:Anti-Infective Agents; D015415:Biomarkers; D024841:Fluoroquinolones; D010879:Piperazines; D015363:Quinolones; D000077734:Gatifloxacin