[I-125]EGF binding in basal ganglia of patients with Parkinson's disease and progressive supranuclear palsy and in MPTP-treated monkeys

Since EGF is known to protect and stimulate the activity of dopaminergic ne urons, an autoradiographic study of [I-125]EGF binding sites was performed in the striatum and pallidal complex in parkinsonian syndromes. The analysi s was performed on posmortem brain tissues of three control subjects, three patients with Parkinson's disease, and three patients with progressive sup ranuclear palsy, another parkinsonian syndrome in which dopaminergic neuron s also degenerate. Since all six patients had been treated with L-Dopa, we also analyzed the effects of this drug in an animal model of Parkinson's di sease. Quantitative analysis of [I-125] EGF binding was performed on the br ains of three control monkeys, nine monkeys rendered parkinsonian by MPTP i ntoxication, three of which were treated with L-Dopa. An increased density of [I-125]EGF binding was observed at anterior levels in the dorsal striatu m, but not in the pallidum, of patients with Parkinson's disease and progre ssive supranuclear palsy. [I-125]EGF binding was unchanged in parkinsonian monkeys whether or not they had been treated with L-Dopa. The data suggest an increased expression of EGFRs in the striatum in chronic parkinsonian sy ndromes but not in acute models of the disease. (C) 1998 Academic Press.