Abnormal influences of passive limb movement on the activity of globus pallidus neurons in parkinsonian monkeys

摘要: Extracellular single unit activity was recorded in the globus pallidus of waking Macaca fascicularis during passive limb movement. The main upper and lower joints were investigated bilaterally. animals either intact or rendered parkinsonian by neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Cell counts showed that at least 90% nigral neurons compacta-type degenerated animals. In animals, only 17% pallidal responded to natural stimulus. As already reported others, responses typically related movement about a contralateral joint one direction. however, more responded, often vigorously, same stimulation. many these elicited than both limbs ipsi-and sides increase number magnitude loss specificity much greater internal segment, where responding quadrupled. These results suggest dopaminergic mechanisms regulate gain selectivity basal ganglia. with decreased functions, excessive unselective motor may explain all 3 major signs parkinsonism: rigidity, tremor akinesia.