| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department of Developmental Physiology, National Institute for Physiological Sciences, Okazaki, Japan
* To whom correspondence should be addressed. E-mail: tendo{at}nips.ac.jp.
The superficial superior colliculus (sSC) is a key station in the sensory processing related to visual salience. The sSC receives cholinergic projections from the parabigeminal nucleus, and previous studies have revealed the presence of several different nicotinic acetylcholine receptor (nAChR) subunits in the sSC. In this study, to clarify the role of the cholinergic inputs to the sSC, we examined current responses induced by ACh in GABAergic and non-GABAergic sSC neurons using in vitro slice preparations obtained from glutamate decarboxylase (GAD) 67-green fluorescent protein (GFP) knock-in mice, in which GFP is specifically expressed in GABAergic neurons. Brief air pressure application of acetylcholine (ACh) elicited nicotinic inward current responses in both GABAergic and non-GABAergic neurons. The inward current responses in the GABAergic neurons were highly sensitive to a selective antagonist for 
3
2- and 62-containing receptors, -conotoxin MII (CtxMII). A subset of these neurons exhibited a faster -bungarotoxin-sensitive inward current component, indicating the expression of 7-containing nAChRs. We also found that the activation of presynaptic nAChRs induced release of GABA, which elicited a burst of miniature inhibitory postsynaptic currents mediated by GABAA receptors in non-GABAergic neurons. This ACh-induced GABA release was mediated mainly by CtxMII-sensitive nAChRs, and resulted from the activation of voltage-dependent calcium channels. Morphological analysis revealed that recorded GFP-positive neurons are interneurons and GFP-negative neurons include projection neurons. These findings suggest that nAChRs are involved in the regulation of GABAergic inhibition, and modulate visual processing in the sSC.
This article has been cited by other articles:
|
|
 |
|
  T. Isa and W. C. Hall Exploring the Superior Colliculus In Vitro J Neurophysiol, November 1, 2009; 102(5): 2581 - 2593. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Maione, L. Cristino, A. L. Migliozzi, A. L. Georgiou, K. Starowicz, T. E. Salt, and V. Di Marzo TRPV1 channels control synaptic plasticity in the developing superior colliculus J. Physiol., June 1, 2009; 587(11): 2521 - 2535. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Sooksawate, K. Isa, and T. Isa Cholinergic Responses in Crossed Tecto-Reticular Neurons of Rat Superior Colliculus J Neurophysiol, November 1, 2008; 100(5): 2702 - 2711. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. A. Goddard, E. I. Knudsen, and J. R. Huguenard Intrinsic Excitability of Cholinergic Neurons in the Rat Parabigeminal Nucleus J Neurophysiol, December 1, 2007; 98(6): 3486 - 3493. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Takahashi, Y. Sugiuchi, and Y. Shinoda Commissural Mirror-Symmetric Excitation and Reciprocal Inhibition Between the Two Superior Colliculi and Their Roles in Vertical and Horizontal Eye Movements J Neurophysiol, November 1, 2007; 98(5): 2664 - 2682. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Marin, C. Salas, E. Sentis, X. Rojas, J. C. Letelier, and J. Mpodozis A Cholinergic Gating Mechanism Controlled by Competitive Interactions in the Optic Tectum of the Pigeon J. Neurosci., July 25, 2007; 27(30): 8112 - 8121. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. H. Lee, T. Sooksawate, Y. Yanagawa, K. Isa, T. Isa, and W. C. Hall Identity of a pathway for saccadic suppression PNAS, April 17, 2007; 104(16): 6824 - 6827. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
