[Changes in monoamine and monoamine metabolites in the nucleus accumbens and locomotor activity caused by p-chloroamphetamine: studies with intracerebral dialysis in freely moving rats].

The effect of i. p. administration of p-chloroamphetamine (PCA) (2mg/kg) on the dopamine (DA), serotonin (5-HT), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) was estimated in freely moving rats by intracerebral dialysis in the nucleus accumbens. Locomotor activity was measured simultaneously by the Animex. After PCA administration, locomotor activity increased significantly in hours 1-2. DA concentration was elevated statistically for 1-2 hours after PCA treatment. And the change of locomotor activity and DA levels were correlated. 5-HT was slightly elevated for 1-2 hours after PCA treatment, although this was not statistical significance through the whole experimental period. These results suggest that an increase in locomotor activity induced by PCA may be explained by activation of the dopaminergic systems in the nucleus accumbens. DOPAC, HVA and 5-HIAA were suppressed significantly during 1-6th. These results suggest that suppression of DOPAC, HVA and 5-HIAA induced by PCA may be explained by PCA's pharmacological effect such as inhibition of monoamineoxidase.