R. Kikura et Y. Nakahara, HAIR ANALYSIS FOR DRUGS OF ABUSE .9. COMPARISON OF DEPRENYL USE AND METHAMPHETAMINE USE BY HAIR ANALYSIS, Biological & pharmaceutical bulletin, 18(2), 1995, pp. 267-272
Deprenyl (DPN) and its metabolites, desmethyl deprenyl (desmethyl DPN)
, methamphetamine (MA) and amphetamine (AP), in the hair of rats and h
umans dosed with DPN were analyzed by selected ion monitoring of gas c
hromatograph-mass spectrometry (GC-MS-SIM). After intraperitoneal admi
nistration of DPN-HCl to rats (10 mg/kg/d, 10d, n = 3), the area under
the concentration versus time curves (AUCs) of DPN and its metabolite
s in the rat plasma were compared with the concentrations of drugs in
rat hair newly grown for 4 weeks. The concentrations of DPN, desmethyl
DPN, MA and AP in the rat hair were 0.97 +/- 0.06, 0.68 +/- 0.02, 14.
04 +/- 0.54 and 13.20 +/- 1.09 ng/mg, and the ratios of the concentrat
ions in the hair to AUCs in their plasma were 0.05: 0.02: 0.3: 0.2, re
spectively. This fact suggested that the incorporation rates of DPN an
d desmethyl DPN into hair from blood were relatively lower than those
of MA and AP. The method was applied to determination of the metabolit
es in scalp hair, beard and urine of humans who orally ingested DPN (1
5 mg/d, 5d, n = 3). DPN (trace level), desmethyl DPN (0.17 - 0.29 ng/m
g), MA (1.30 - 2.25 ng/mg) and AP (0.42 - 0.99 ng/mg) were detected in
the scalp hair collected three weeks after the first intake, while in
beard or urine these drugs were detected only for a few days. It was
concluded that DPN use could be distinguished from MA abuse retrospect
ively by the detection of DPN and/or desmethyl DPN in scalp hair. It w
as also shown that the ratio of AP to MA in hair or enantiomeric compo
sitions of MA in hair would allow distinction of DPN use from MA use.