HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Mori, K Articles by Shepherd, G M Search for Related Content PubMed PubMed Citation Articles by Mori, K Articles by Shepherd, G M

1. An in vitro preparation of the turtle olfactory bulb has been developed. Electrophysiological properties of mitral cells in the isolated bulb have been analysed with intracellular recordings. 2. Mitral cells have been driven antidromically from the lateral olfactory tract, or activated directly by current injection. Intracellular injections of horseradish peroxidase (HRP) show that turtle mitral cells have long secondary dendrites that extend up to 1800 micrometer from the cell body and reach around half of the bulbar circumference. There are characteristically two primary dendrites, each supplying separate olfactory glomeruli. 3. Using intracellular current pulses, the whole-neurone resistance was found to range from 33 to 107 M omega. The whole-neurone charging transient had a slow time course. The membrane time constant was estimated to be 24-93 msec by the methods of Rall. The electrotonic length of the mitral cell equivalent cylinder was estimated by Rall's methods to be 0.9-1.9. 4. The spikes generated by turtle mitral cells were only partially blocked by tetrodotoxin (TTX) in the bathing medium. The TTX-resistant spikes were enhanced in the presence of tetraethylammonium (TEA), and blocked completely by cobalt. 5. The implications of the electrical properties for impulse generation in turtle mitral cells are discussed. The mitral cells have dendrodendritic synapses onto granule cells, and the TTX-resistant spikes may therefore play an important role in presynaptic transmitter release at these synapses.

This article has been cited by other articles:

				R. F. Galan, N. Fourcaud-Trocme, G. B. Ermentrout, and N. N. Urban Correlation-induced synchronization of oscillations in olfactory bulb neurons. J. Neurosci., April 5, 2006; 26(14): 3646 - 3655. [Abstract] [Full Text] [PDF]

				G. Pinato and J. Midtgaard Dendritic Sodium Spikelets and Low-Threshold Calcium Spikes in Turtle Olfactory Bulb Granule Cells J Neurophysiol, March 1, 2005; 93(3): 1285 - 1294. [Abstract] [Full Text] [PDF]

				G. Pinato and J. Midtgaard Regulation of Granule Cell Excitability by a Low-Threshold Calcium Spike in Turtle Olfactory Bulb J Neurophysiol, November 1, 2003; 90(5): 3341 - 3351. [Abstract] [Full Text] [PDF]

				G. Lowe Inhibition of Backpropagating Action Potentials in Mitral Cell Secondary Dendrites J Neurophysiol, July 1, 2002; 88(1): 64 - 85. [Abstract] [Full Text] [PDF]

				M. Wachowiak, L. B. Cohen, and M. R. Zochowski Distributed and Concentration-Invariant Spatial Representations of Odorants by Receptor Neuron Input to the Turtle Olfactory Bulb J Neurophysiol, February 1, 2002; 87(2): 1035 - 1045. [Abstract] [Full Text] [PDF]

				D. Mellon Jr. Convergence of Multimodal Sensory Input Onto Higher-Level Neurons of the Crayfish Olfactory Pathway J Neurophysiol, December 1, 2000; 84(6): 3043 - 3055. [Abstract] [Full Text] [PDF]

				D. Mellon Jr. and C. J. Wheeler Coherent Oscillations in Membrane Potential Synchronize Impulse Bursts in Central Olfactory Neurons of the Crayfish J Neurophysiol, March 1, 1999; 81(3): 1231 - 1241. [Abstract] [Full Text] [PDF]