Biochemical findings in a case of parkinsonism secondary to brain tumor

Neuropathological and biochemical studies were performed in a patient with craniopharyngioma and a long history of parkinsonism. Morphological examination revealed atrophy of the substantia nigra without Lewy bodies. Both th caudate and putamen nuclei showed moderate loss of large cells with glial proliferation. There was a notable decrease in dopamine and its metabolites and a reduction in norepinephrine content in both the caudate and putamen nuclei. Less consistent changes were found in serotonin and amino acid levels. Dopamine receptors, evaluated as 3H-spiperone binding sites, were unchanged in the putamen but decreased to 30% of control values in the caudate. The findings suggest that parkinsonism was caused by the brain tumor, which damaged both the presynaptic dopaminergic nigrostriatal neurons and the postsynaptic dopamine receptors.