The present study investigates the effects of acute and chronic administrat
ion of triazolam in albino rats on glycine levels in different brain areas.
Three experiments were conducted. In the first, five groups of rats were a
cutely treated with different doses of triazolam (0.25 mg/kg-4.0mg/kg i.p.)
. In the second experiment, rats were treated chronically by a single daily
dose of triazolam (started by 0.25 mg/kg and increased by time to 1.0mg/kg
) for 5 weeks, simulating clinical use. In the third, rats were treated chr
onically three daily doses of triazolam (started by 0.25mg/kg and increased
by time to 0.5 mg/kg) for 20 days, simulating a form of drug abuse. Brain
levels of glycine and plasma levels of triazolam were measured using HPLC t
echnique. The acute triazolam administration produced an increase in glycin
e levels in almost all brain areas studied. The chronic administration of s
ingle daily dose of triazolam produced normal glycine levels in most of the
brain areas; this indicates the development of tolerance to glycine conten
t increasing action of triazolam. The chronic administration of three daily
doses of triazolam produced a decrease in glycine levels in almost all bra
in regions studied, which might be a prerequisite for oncoming withdrawal s
yndrome.