| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
The Journal of Neurophysiology Vol. 87 No. 4 April 2002, pp. 1993-2008
Copyright ©2002 by the American Physiological Society
Department of Physiology and Neuroscience, New York University School of Medicine, New York, New York 10016
Lang, Eric J.
GABAergic and Glutamatergic Modulation of Spontaneous and
Motor-Cortex-Evoked Complex Spike Activity. J. Neurophysiol. 87: 1993-2008, 2002. Olivocerebellar activity is
organized such that synchronous complex spikes occur primarily among
Purkinje cells located within the same parasagittally oriented strip of
cortex. Previous findings have shown that this synchrony distribution
is modulated by the release of GABA and glutamate within the inferior
olive, which probably act by controlling the efficacy of the
electrotonic coupling between olivary neurons. The relative strengths
of these two neurotransmitters in modulating the patterns of synchrony
were compared by obtaining multiple electrode recordings of spontaneous
crus 2a complex spike activity during intraolivary injection of
solutions containing a GABAA (picrotoxin) and/or
AMPA
[1,2,3,4-tetrahydro-6-nitro-2,3-dioxo-benzo[f]quinoxaline-7-sulfonamide disodium (NBQX)] receptor antagonist. Injection of either antagonist led to increased synchrony between cells located within the same parasagittally oriented 
250-µm-wide cortical strip. Picrotoxin also increased complex spike synchrony among cells located in different
cortical strips, leading to a less prominent banding pattern, whereas
injections of NBQX tended to decrease complex spike synchrony among
such cells, enhancing the banding pattern. The relative strength of
these two classes of olivary afferents was assessed by first injecting
one of the antagonists alone and then in combination with the other.
The enhanced banding pattern of complex spike synchrony following
injection of NBQX alone remained during the subsequent combined
injection of both antagonists. Furthermore, the widespread
synchronization of complex spike activity following injection of
picrotoxin alone was partially or completely reversed by combined
injection of picrotoxin and NBQX. Changes in the climbing fiber reflex
induced by the intraolivary injections paralleled the changes observed
for spontaneous complex spike activity, indicating that the effects of
picrotoxin and NBQX on the synchrony distribution reflect changes in
the pattern of effective coupling of inferior olivary neurons and
demonstrating that synchronous complex spike activity does not require
simultaneous excitatory input to olivary cells. Finally the pattern of
synchrony during motor cortical stimulation was examined. It was found
that the patterns of synchrony for motor-cortex-evoked complex spike
activity were similar to those of spontaneous activity, indicating an
important role for electrotonic coupling in determining the response of the olivocerebellar system to afferent input. Moreover, intraolivary injections of picrotoxin increased the spatial distribution of the
evoked response. In sum, the results provide evidence for the
hypothesis that electrotonic coupling of inferior olivary neurons via
gap junctions is the mechanism underlying complex spike synchrony and
that this coupling plays an important role in determining the responses
of the olivocerebellar system to synaptic input.
This article has been cited by other articles:
|
|
 |
|
  I. Ozden, M. R. Sullivan, H. M. Lee, and S. S.-H. Wang Reliable Coding Emerges from Coactivation of Climbing Fibers in Microbands of Cerebellar Purkinje Neurons J. Neurosci., August 26, 2009; 29(34): 10463 - 10473. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. A. Jacobson, I. Lev, Y. Yarom, and D. Cohen Invariant phase structure of olivo-cerebellar oscillations and its putative role in temporal pattern generation PNAS, March 3, 2009; 106(9): 3579 - 3584. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Wada, Y. Kishimoto, D. Watanabe, M. Kano, T. Hirano, K. Funabiki, and S. Nakanishi Conditioned eyeblink learning is formed and stored without cerebellar granule cell transmission PNAS, October 16, 2007; 104(42): 16690 - 16695. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Khosrovani, R. S. Van Der Giessen, C. I. De Zeeuw, and M. T. G. De Jeu In vivo mouse inferior olive neurons exhibit heterogeneous subthreshold oscillations and spiking patterns PNAS, October 2, 2007; 104(40): 15911 - 15916. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Chorev, Y. Yarom, and I. Lampl Rhythmic Episodes of Subthreshold Membrane Potential Oscillations in the Rat Inferior Olive Nuclei In Vivo J. Neurosci., May 9, 2007; 27(19): 5043 - 5052. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. M. Ackert, S. H. Wu, J. C. Lee, J. Abrams, E. H. Hu, I. Perlman, and S. A. Bloomfield Light-induced changes in spike synchronization between coupled ON direction selective ganglion cells in the mammalian retina. J. Neurosci., April 19, 2006; 26(16): 4206 - 4215. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. J. Lang, I. Sugihara, and R. Llinas Olivocerebellar modulation of motor cortex ability to generate vibrissal movements in rat J. Physiol., February 15, 2006; 571(1): 101 - 120. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. A. Blenkinsop and E. J. Lang Block of Inferior Olive Gap Junctional Coupling Decreases Purkinje Cell Complex Spike Synchrony and Rhythmicity J. Neurosci., February 8, 2006; 26(6): 1739 - 1748. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Leznik and R. Llinas Role of Gap Junctions in Synchronized Neuronal Oscillations in the Inferior Olive J Neurophysiol, October 1, 2005; 94(4): 2447 - 2456. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Hewitt, R. Barrie, M. Graham, K. Bogus, J. C. Leiter, and J. S. Erlichman Ventilatory effects of gap junction blockade in the RTN in awake rats Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2004; 287(6): R1407 - R1418. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. J. Lang and J. Rosenbluth Role of Myelination in the Development of a Uniform Olivocerebellar Conduction Time J Neurophysiol, April 1, 2003; 89(4): 2259 - 2270. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
