Optogenetic manipulation of cerebellar Purkinje cell activity in vivo

Purkinje cells (PCs) are the sole output neurons of the cerebellar cortex. Although their anatomical connections and physiological response properties have been extensively studied, the causal role of their activity in behavioral, cognitive and autonomic functions is still unclear because PC activit...

Full description

Saved in:

Bibliographic Details
Published in:	PloS one 2011-08, Vol.6 (8), p.e22400-e22400
Main Authors:	Tsubota, Tadashi, Ohashi, Yohei, Tamura, Keita, Sato, Ayana, Miyashita, Yasushi
Format:	Article
Language:	eng
Subjects:	Analysis Animals Autonomic nervous system Biology Blood Pressure Cats Cell Line Cerebellar Cortex - cytology Cerebellum Cognitive ability Electrophysiology Gene expression Genetics Humans Illumination Immunohistochemistry In vivo methods and tests Information processing Lasers Lentivirus - genetics Light Male Medicine Nervous system Neurons Optics Photoinhibition Physiology Plasmids Promoter Regions, Genetic - genetics Proteins Purkinje cells Purkinje Cells - metabolism Purkinje Cells - radiation effects Rats Rats, Wistar Regulatory sequences Rhodopsin - genetics Rhodopsin - metabolism Rodents
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Purkinje cells (PCs) are the sole output neurons of the cerebellar cortex. Although their anatomical connections and physiological response properties have been extensively studied, the causal role of their activity in behavioral, cognitive and autonomic functions is still unclear because PC activity cannot be selectively controlled. Here we developed a novel technique using optogenetics for selective and rapidly reversible manipulation of PC activity in vivo. We injected into rat cerebellar cortex lentiviruses expressing either the light-activated cationic channel channelrhodopsin-2 (ChR2) or light-driven chloride pump halorhodopsin (eNpHR) under the control of the PC-specific L7 promoter. Transgene expression was observed in most PCs (ChR2, 92.6%; eNpHR, 95.3%), as determined by immunohistochemical analysis. In vivo electrophysiological recordings showed that all light-responsive PCs in ChR2-transduced rats increased frequency of simple spike in response to blue laser illumination. Similarly, most light-responsive PCs (93.8%) in eNpHR-transduced rats decreased frequency of simple spike in response to orange laser illumination. We then applied these techniques to characterize the roles of rat cerebellar uvula, one of the cardiovascular regulatory regions in the cerebellum, in resting blood pressure (BP) regulation in anesthetized rats. ChR2-mediated photostimulation and eNpHR-mediated photoinhibition of the uvula had opposite effects on resting BP, inducing depressor and pressor responses, respectively. In contrast, manipulation of PC activity within the neighboring lobule VIII had no effect on BP. Blue and orange laser illumination onto PBS-injected lobule IX didn't affect BP, indicating the observed effects on BP were actually due to PC activation and inhibition. These results clearly demonstrate that the optogenetic method we developed here will provide a powerful way to elucidate a causal relationship between local PC activity and functions of the cerebellum.
ISSN:	1932-6203 1932-6203