Methadone, monoamine oxidase, and depression: opioid distribution and acute effects on enzyme activity

Journal Article · Thu Sep 01 04:00:00 EDT 1983 · Biol. Psychiatry; (United States)

OSTI ID:6747513

Kaufmann, C A; Kreek, M J; Raghunath, J; Arns, P

Narcotic withdrawal is often accompanied by an atypical depression which responds to resumption of narcotics. It was hypothesized that methadone might exert its antidepressant effects through monoamine oxidase (MAO) inhibition. The current study examined /sub 3/H-methadone distribution in rat brain and effects on regional MAO activity with acute doses (2.5 mg/kg) which approximate those found during chronic methadone maintenance in man. Limbic areas (amygdala, basomedial hypothalamus, caudate-putamen, hippocampus, preoptic nucleus), as well as pituitary and liver were assayed for MAO activity and methadone concentration. MAO activities did not differ significantly in acute methadone or saline-treated cage-mates at 1 or 24 hr. The concentrations of methadone at 1 hr ranged between 17 and 223 ng/100 mg wet wt tissue in the preoptic nucleus and pituitary, respectively. No significant correlation was found between change in MAO activity (MAO methadone/MAO saline) and methadone concentration in any region at 1 or 24 hr. This study does not support the hypothesis that methadone acts as an antidepressant through MAO inhibition, at least not following acute administration of this exogenous opioid.

• Research Organization: Rockefeller Univ., New York, NY
• OSTI ID: 6747513
• Journal Information: Biol. Psychiatry; (United States), Journal Name: Biol. Psychiatry; (United States) Vol. 18:9; ISSN BIPCB
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
BIOASSAY
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL EFFECTS
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
CENTRAL NERVOUS SYSTEM DEPRESSANTS
DIGESTIVE SYSTEM
DISTRIBUTION
DOSE-RESPONSE RELATIONSHIPS
DRUGS
ENDOCRINE GLANDS
ENZYMES
GLANDS
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
LIVER
MAMMALS
METHADONE HYDROCHLORIDE
NARCOTICS
NERVOUS SYSTEM
ORGANS
OXIDOREDUCTASES
PITUITARY GLAND
RATS
REACTION KINETICS
RODENTS
TISSUE DISTRIBUTION
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES