Cerebrovascular and metabolic uncoupling in the caudate-putamen following unilateral lesion of the mesencephalic dopaminergic neurons in the rat

Abstract

Changes in local cerebral blood flow (lCBF) and local cerebral glucose utilization (lCGU) were assessed in dopaminergic primary target areas in the rat 6 weeks after unilateral lesion of dopaminergic neurons within the substantia nigra pars compacta (SNc) and adjacent ventrotegmental area (VTA) using 6-hydroxydopamine (6-OHDA). lCBF and lCGU were determined using the autoradiographic [14C]iodoantipyrine and [14C]2-deoxyglucose method. Dopaminergic deafferentation provoked a marked unilateral lCBF decrease in the dorso-lateral portion of the rostral caudate-putamen. The decrease in lCBF was not associated with significant changes in glucose metabolism. Thus, lesions of dopaminergic afferents to the caudate-putamen appear to provoke a sustained decrease in basal blood flow with unchanged local metabolic activity.