The present study investigates the effects of acute and chronic administration of
triazolam in albino rats on
glycine levels in different brain areas. Three experiments were conducted. In the first, five groups of rats were acutely treated with different doses of
triazolam (0.25 mg/kg-4.0 mg/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 1.0 mg/kg) for 5 weeks, simulating clinical use. In the third, rats were treated chronically three daily doses of
triazolam (started by 0.25 mg/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 technique. The acute
triazolam administration produced an increase in
glycine levels in almost all brain areas studied. The chronic administration of single daily dose of
triazolam produced normal
glycine levels in most of the brain areas; this indicates the development of tolerance to
glycine content increasing action of
triazolam. The chronic administration of three daily doses of
triazolam produced a decrease in
glycine levels in almost all brain regions studied, which might be a prerequisite for oncoming withdrawal syndrome.