|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department of Physiology, Emory University, Atlanta, GA, USA
* To whom correspondence should be addressed. E-mail: shochman{at}physio.emory.edu.
Lamina I is a sensory relay region containing projection cells and local interneurons involved in thermal and nociceptive signaling. These neurons differ in morphology, sensory response modality, and firing characteristics. We examined intrinsic properties of mouse lamina I GABAergic neurons expressing enhanced green fluorescent protein (EGFP). GABAergic neuron identity was confirmed by a high correspondence between GABA immunolabeling and EGFP fluorescence. Morphologies of these EGFP+/GABA+ cells were multipolar (65%), fusiform (31%), and pyramidal (4%). In whole-cell recordings, cells fired a single spike (44%), tonically (35%), or an initial burst (21%) in response to current steps, representing a subset of reported lamina I firing properties. Membrane properties of tonic and initial burst cells were indistinguishable and these neurons may represent one functional population since, in individual neurons, their firing patterns could interconvert. Single spike cells were less excitable with lower membrane resistivity and higher rheobase. Most fusiform cells (64%) fired tonically while most multipolar cells (56%) fired single spikes. In summary, lamina I inhibitory interneurons are functionally divisible into at least 2 major groups both of which presumably function to limit excitatory transmission.
This article has been cited by other articles:
![]() |
J. Golowasch, G. Thomas, A. L. Taylor, A. Patel, A. Pineda, C. Khalil, and F. Nadim Membrane Capacitance Measurements Revisited: Dependence of Capacitance Value on Measurement Method in Nonisopotential Neurons J Neurophysiol, October 1, 2009; 102(4): 2161 - 2175. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Sandkuhler Models and Mechanisms of Hyperalgesia and Allodynia Physiol Rev, April 1, 2009; 89(2): 707 - 758. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. B. Lu, J. E. Biggs, M. J. Stebbing, S. Balasubramanyan, K. G. Todd, A. Y. Lai, W. F. Colmers, D. Dawbarn, K. Ballanyi, and P. A. Smith Brain-derived neurotrophic factor drives the changes in excitatory synaptic transmission in the rat superficial dorsal horn that follow sciatic nerve injury J. Physiol., March 1, 2009; 587(5): 1013 - 1032. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. A. Daniele and A. B. MacDermott Low-Threshold Primary Afferent Drive onto GABAergic Interneurons in the Superficial Dorsal Horn of the Mouse J. Neurosci., January 21, 2009; 29(3): 686 - 695. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. J. Dougherty and S. Hochman Spinal Cord Injury Causes Plasticity in a Subpopulation of Lamina I GABAergic Interneurons J Neurophysiol, July 1, 2008; 100(1): 212 - 223. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. B. Lu, K. Ballanyi, W. F. Colmers, and P. A. Smith Neuron type-specific effects of brain-derived neurotrophic factor in rat superficial dorsal horn and their relevance to 'central sensitization' J. Physiol., October 15, 2007; 584(2): 543 - 563. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. M. Wilson, D. A. Dombeck, M. Diaz-Rios, R. M. Harris-Warrick, and R. M. Brownstone Two-Photon Calcium Imaging of Network Activity in XFP-Expressing Neurons in the Mouse J Neurophysiol, April 1, 2007; 97(4): 3118 - 3125. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. W. Bagnall, R. J. Stevens, and S. du Lac Transgenic Mouse Lines Subdivide Medial Vestibular Nucleus Neurons into Discrete, Neurochemically Distinct Populations J. Neurosci., February 28, 2007; 27(9): 2318 - 2330. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Balasubramanyan, P. L. Stemkowski, M. J. Stebbing, and P. A. Smith Sciatic Chronic Constriction Injury Produces Cell-Type-Specific Changes in the Electrophysiological Properties of Rat Substantia Gelatinosa Neurons J Neurophysiol, August 1, 2006; 96(2): 579 - 590. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |