Biochemical characterization of the dopaminergic innervation of the rat septum

The septum has been found to possess a highly affinity dopamine (DA) uptake system, significant levels of its metabolite dihydroxyphenylacetic acid (DOPAC), and non-adenyl-cyclase (AC) linked, [ 3H]-spiroperidol ([ 3H]SPIR)-labelled specific depaminergic receptors. Treatment of the animals with either apomorphine (APO) or haloperidol (HAL) induced a decrease and an increase of DOPAC levels respectively. The intracerebroventricular (i.v.t.) administration of the opioid peptide d-ala 2-methionine-enkephalin (DALA) induced catalepsy with a concomitant rise of DOPAC levels. These results allow a better biochemical characterization of the septal dopaminergic system, and indicate that such system might be involved in the behavioral and hormonal influences exerted by this limbic brain area.