Nov 12, 1993

A high-dose methamphetamine regimen results in long-lasting deficits on performance of a reaction-time task

Brain Research
J B RichardsL S Seiden


Rats were treated with a high-dose methamphetamine (METH) regimen (50 mg/kg 3 times at 8-h intervals). Three weeks after treatment, they were trained on a reaction-time task. METH-treated rats failed to improve over a 3-month test period, while controls demonstrated a gradual increase in reaction-time speed over the same test period. METH treatment resulted in a significant dopamine depletions in the caudate/putamen and nucleus accumbens/olfactory tubercle; significant serotonin depletions in caudate/putamen, nucleus accumbens/olfactory tubercle, somatosensory cortex, amygdala and hippocampus. In contrast to the decreases observed in other brain regions, serotonin levels were significantly greater than controls in the hypothalamus. It is suggested that the behavioral impairment in the METH-treated animals is due to (a) serotonin and/or dopamine depletions or (b) abnormal or hyper-innervation of serotonin to the hypothalamus.

Mentioned in this Paper

Reaction Time
Serotonin Measurement
Muscle Innervation, Function
Methamphetamine Measurement
5-methyltetrahydrofolate-homocysteine S-methyltransferase Activity
Nerve Supply
Olfactory tubercle
Entire Putamen
Genus Hippocampus

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