Dopamine depletion protects striatal neurons from ischemia-induced cell death.

Infusion of the dopamine neurotoxin 6-hydroxydopamine, unilaterally into the substantia nigra of rats, resulted in a unilateral depletion of dopamine in the ipsilateral striatum. When these rats were subjected to global forebrain ischemia by the four-vessel occlusion technique, there was a significant protection of the dopamine depleted striatum from the ischemia-induced loss of medium sized neurons seen in the intact striatum. These results imply a role for dopamine in ischemia-induced striatal cell death.