METHAMPHETAMINE-INDUCED NUCLEAR C-FOS IN RAT-BRAIN REGIONS

To explore the possible robust changes in neuronal activity in dopamin e-poor brain regions after an indirect dopamine agonist, methamphetami ne, we have investigated its effects on c-fos expression in rat brain using immunocytochemistry of c-Fos. Intraperitoneal injection of metha mphetamine (1.6-4.8 mg/kg), but not of saline, induced a widespread nu clear c-Fos-like immunoreactivity in the pyriform cortex and olfactory tubercle with greatest density followed by the II-VI layers of the ne ocortex, amygdala, hypothalamus, thalamus, nucleus accumbens and stria tum. These expression patterns resemble those elicited by amphetamine and suggest that not only the dopamine-rich subcortical regions but al so the cerebral cortex may play a crucial role in behavioral abnormali ty induced by methamphetamine.