Methamphetamine-induced behavioral effects and releases of brain catecholamines and brain concentrations of methamphetamine in mice.
The characteristic behavioral effect of methamphetamine (MA) at 2.5 mg/kg was enhanced locomotor activity which lasted over 2.5 hr. At 10.0 mg/kg MA, stereotyped behavior was predominant and lasted over 3 hr. The behavioral effect of 5.0 mg/kg MA was of the mixed type. MA at 5.0 and 10.0 mg/kg lowered the brain NE level from 2 hr after drug treatment, while the accumulation of MHPG-SO4 was increased over 2 hr at 2.5 and 5.0 mg/kg MA. The accumulation of HVA was significantly increased at 10.0 mg/kg MA over 3 hr. Accordingly, the behavioral effects of MA at the earlier period were compatible with the biochemical effects of MA. The behavioral effects during the 2- to 4-hr period, however, seem to be unrelated to the actions on brain catecholamines. Measurement of brain MA concentrations revealed that approx. 2 micrograms/g in the brain may be necessary to produce enhanced locomotor activity and the increased accumulation of brain MHPG-SO4. It appeared that approx. 8 to 9 micrograms/g MA in the brain was required to produce characteristic stereotyped behavior and the increased accumulation of HVA. Therefore, the behavioral and biochemical effects of MA were correlated with the brain MA concentrations.
D000661:Amphetamine / Q000378:metabolism; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D001921:Brain / Q000378:metabolism; D001923:Brain Chemistry / Q000187:drug effects*; D002395:Catecholamines / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism; D006719:Homovanillic Acid / Q000378:metabolism; D006801:Humans; D008297:Male; D008694:Methamphetamine / Q000378:metabolism / Q000494:pharmacology*; D008734:Methoxyhydroxyphenylglycol / Q000378:metabolism; D051379:Mice; D009638:Norepinephrine / Q000378:metabolism; D013239:Stereotyped Behavior / Q000187:drug effects; D013997:Time Factors
D002395:Catecholamines; D008694:Methamphetamine; D008734:Methoxyhydroxyphenylglycol; D000661:Amphetamine; D004298:Dopamine; D009638:Norepinephrine; D006719:Homovanillic Acid