in the substantia nigra of anesthetized and awake monkeys , presumptive dopamine cells of the pars compacta were electrophysiologically discriminated against non-dopaminergic cells of the pars reticulata by their lower discharge rate ( 0.5-8 vs 20-130 imp./s ) , their longer impulse duration ( means 2.05 vs 0.92 ms ) , and their exclusive depression following systemic injection of the dopamine agonist apomorphine ( 24 out of 30 compacta neurons at 0.05-0.1 mg/kg s.c. ) .
C0038590
substantia nigra
C0175412
pars compacta