Purkinje cell BKchannel ablation induces abnormal rhythm in deep cerebellar nuclei and prevents LTD

Purkinje cells (PC) control deep cerebellar nuclei (DCN), which in turn inhibit inferior olive nucleus, closing a positive feedback loop via climbing fibers. PC highly express potassium BK channels but their contribution to the olivo-cerebellar loop is not clear. Using multiple-unit recordings in al...

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Detalhes bibliográficos
Autores: Cheron, Guy, Márquez-Ruiz, Javier, Cheron, Julian, Prigogine, Cynthia, Ammann, Claudia, Lukowski, Robert, Ruth, Peter, Dan, Bernard
Formato: artículo
Fecha de publicación:2018
País:España
Recursos:Universidad Camilo José Cela (UCJC)
Repositorio:Depósito Digital e-UCJC
OAI Identifier:oai:repositorio.ucjc.edu:20.500.12020/1163
Acesso em linha:http://hdl.handle.net/20.500.12020/1163
Access Level:acceso abierto
Palavra-chave:Ciencias Biomédicas
Cerebellum
BK Channel
Purkinje Cells
Ataxia
2490.01 Neurofisiología
2302.21 Biología Molecular
Descrição
Resumo:Purkinje cells (PC) control deep cerebellar nuclei (DCN), which in turn inhibit inferior olive nucleus, closing a positive feedback loop via climbing fibers. PC highly express potassium BK channels but their contribution to the olivo-cerebellar loop is not clear. Using multiple-unit recordings in alert mice we found in that selective deletion of BK channels in PC induces a decrease in their simple spike firing with a beta-range bursting pattern and fast intraburst frequency (~200 Hz). To determine the impact of this abnormal rhythm on the olivo-cerebellar loop we analyzed simultaneous rhythmicity in different cerebellar structures. We found that this abnormal PC rhythmicity is transmitted to DCN neurons with no effect on their mean firing frequency. Long term depression at the parallel-PC synapses was altered and the intra-burst complex spike spikelets frequency was increased without modification of the mean complex spike frequency in BK-PC−/− mice. We argue that the ataxia present in these conditional knockout mice could be explained by rhythmic disruptions transmitted from mutant PC to DCN but not by rate code modification only. This suggests a neuronal mechanism for ataxia with possible implications for human disease.