title: Subthalamotomy improves MPTP-induced parkinsonism in monkeys.
abstract: Hyperactivity of the subthalamic nucleus (STN) is major characteristic of parkinsonism secondary to substantia nigra lesions. Interruption of the STN-internal pallidum (GPi) pathway is a new stereotactic target for Parkinson's disease. We have studied the antiparkinsonian efficacy of STN lesions in MPTP-treated monkeys. Four rhesus monkeys were made parkinsonian by MPTP (i.v. 0.15 +/- 1 mg/kg) administration over 3 months. Unilateral subthalamotomy (kainic acid) was performed by a standard stereotactic method. Severity was rated from 0 (normal) to V by fine manual motor tests. Three monkeys (severity state III/IV) showed marked improvement in spontaneous activity, facial expression and manual dexterity bilaterally but significantly greater in the limb contralateral to the lesion. Mild hemichorea was present in 2 and hemiballism in one. L-Dopa treatment (50 mg b.i.d.) enhanced the hemidyskinesias moderately. The therapeutic effect has persisted for over 8 months postsurgery. Monkey No.4 (severity stage V) showed chorea in the lower limb contralateral to the lesion but no improvement and died a few days later. Subthalamotomy improves parkinsonism in moderately severe parkinsonian monkeys. Dyskinesia might be a persistent complication.
authors.affiliation: Neurosurgical Department, Hospital de Navarra, Pamplona, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Guridi
authors.forename: M T
authors.initials: MT
authors.lastname: Herrero
authors.forename: R
authors.initials: R
authors.lastname: Luquin
authors.forename: J
authors.initials: J
authors.lastname: Guillen
authors.forename: J A
authors.initials: JA
authors.lastname: Obeso
mesh_terms: D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D000818:Animals; D008253:Macaca mulatta; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000601:surgery*; D013238:Stereotaxic Techniques; D013787:Thalamic Nuclei / Q000601:surgery*; D016896:Treatment Outcome
chemical_list: D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine