Electrophysiological investigation of thalamic neuronal mechanisms of motor disorders in parkinsonism: an influence of D2ergic transmission blockade on excitation and inhibition of relay neurons in motor thalamic nuclei of cat.

In acute experiments on cats anaesthetized with ketamine (25 mg/kg, i.m.) and immobilized with myorelaxine (2 mg/kg, i.

Influence of N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced injury of dopaminergic nigrostriatal system on movement components of the instrumental reflex and motor thalamic neurons' reactions in the cat.

Peculiarities of excitation and inhibition in ventral lateral and ventral anterior thalamic neurons were studied in cats with movement disorders (bradykinesia and muscle rigidity) induced by injury of nigrostriatal dopaminergic neurons with neurotoxin N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (5 mg/kg daily, intramuscularly for five days). As was shown in chronic experiments, mean discharge frequency of neurons related to initiation of upper limb movements increased. Excitation of these neurons coincided with movement initiation, flexion and extension becoming more prominent and prolonged as compared with normal animals.