The influence of insulin hypoglycemia on central dopaminergic structures of the rat.

Daily administration of insulin, 2 U/kg/day for 9 days, leads to a marked increase in the activity of central dopaminergic structures, reflected by an increase in the apomorphine or amphetamine-induced stereotypy and a decrease in fluphenazine-induced catalepsy. These changes are accompanied by a depression of cerebral dopamine and noradrenaline levels and a depression of noradrenaline utilization in the brain.