Open AccessMethamphetamine-induced behavioral effects and releases of brain catecholamines and brain concentrations of methamphetamine in mice.
Author(s) -
Yasumitsu Yamanaka,
Toshinori Yamamoto,
Toru Egashira
Publication year - 1983
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - English
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.33.33
Subject(s) - methamphetamine , endocrinology , medicine , period (music) , locomotor activity , chemistry , psychology , pharmacology , physics , acoustics
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.