Neuronal activity in the globus pallidus of multiple system atrophy patients.
The pathophysiological changes in neural activity that characterize multiple system atrophy (MSA) are largely unknown. We recorded the activity of pallidal neurons in 3 patients with clinical and radiological features of MSA who underwent unilateral microelectrode-guided pallidotomy for disabling parkinsonism. Findings in these patients were compared with 4 control patients with a clinical diagnosis of Parkinson's disease (PD). The position, firing rates, and firing patterns of single neurons in the pallidal complex were analyzed in both MSA and PD patients. The mean spontaneous firing rate of neurons in the internal segment of the globus pallidus internus (GPii) was significantly lower in MSA than in PD patients. There were no significant differences between MSA and PD patients, however, in firing rates of neurons in the external globus pallidus (GPe) or in the external segment of GPi (GPie). In addition, no significant differences in firing pattern were found between MSA and PD patients. In conclusion, this study has shown that firing rates of neurons in GPii but not in GPie and GPe are different in MSA patients compared with that in PD patients, a finding that may reflect the poor clinical results of pallidotomy reported in patients with MSA.
Pereira
Luiz C M
LC
Department of Surgery, Division of Neurosurgery, University of Toronto, Toronto, Ontario, Canada.
Palter
Vanessa N
VN
Lang
Anthony E
AE
Hutchison
William D
WD
Lozano
Andres M
AM
Dostrovsky
Jonathan O
JO
D000328:Adult; D000368:Aged; D000927:Anticonvulsants / Q000627:therapeutic use; D000978:Antiparkinson Agents / Q000627:therapeutic use; D005260:Female; D005917:Globus Pallidus / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D008297:Male; D008839:Microelectrodes; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000503:physiopathology* / Q000601:surgery; D019635:Neurosurgical Procedures / Q000295:instrumentation; D010300:Parkinson Disease / Q000188:drug therapy / Q000503:physiopathology* / Q000601:surgery
D000927:Anticonvulsants; D000978:Antiparkinson Agents; D007980:Levodopa