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 Clements, J D Articles by Redman, S J Search for Related Content PubMed PubMed Citation Articles by Clements, J D Articles by Redman, S J

Experimental Neurology Unit, John Curtin School of Medical Research, Australian National University, ACT.

1. Spinal alpha-motoneurones were injected with horseradish peroxidase after measuring their voltage response to a brief current pulse and their current response to a small voltage step. 2. The morphology of each motoneurone was reconstructed from serial sections. The diameters and lengths of dendritic segments were used to build a compartmental model of each neurone's electrotonic structure. The specific resistivity of the membrane (Rm) was assumed to be constant throughout the dendrites, but it was lowered for the somatic membrane by the introduction of a somatic shunt resistance. 3. The specific resistances of the somatic and dendritic membrane were adjusted in the compartmental model until the responses of the model to the same current and voltage steps as those used in the experiment gave the best fits to the recorded transients. Satisfactory fits were obtained for six out of seven motoneurones. Dendritic Rm varied from 7 to 35 k omega cm2 and somatic Rm varied from 100 to 420 omega cm2. The dendritic Rm was 100-300 times the somatic Rm for different neurones. 4. The calculated dendritic Rm was used to determine the geometric profile of the equivalent dendritic cable. This was found to be an approximately uniform cylinder for about 0.5 lambda and thereafter to taper rapidly to a final termination at 2-3 lambda from the soma. 5. The results indicate that motoneurone dendrites are more electrically compact than was hitherto believed. The different Rm values for somatic and dendritic membrane, and the tapering of the dendritic cable, means that the cable model developed by Rall (1959, 1964) must be revised to take account of these spatial and electrical non-uniformities.

This article has been cited by other articles:

				L. Sarid, R. Bruno, B. Sakmann, I. Segev, and D. Feldmeyer Modeling a layer 4-to-layer 2/3 module of a single column in rat neocortex: Interweaving in vitro and in vivo experimental observations PNAS, October 9, 2007; 104(41): 16353 - 16358. [Abstract] [Full Text] [PDF]

				C. Schmidt-Hieber, P. Jonas, and J. Bischofberger Subthreshold Dendritic Signal Processing and Coincidence Detection in Dentate Gyrus Granule Cells J. Neurosci., August 1, 2007; 27(31): 8430 - 8441. [Abstract] [Full Text] [PDF]

				N. P. Shapiro and R. H. Lee Synaptic Amplification Versus Bistability in Motoneuron Dendritic Processing: A Top-Down Modeling Approach J Neurophysiol, June 1, 2007; 97(6): 3948 - 3960. [Abstract] [Full Text] [PDF]

				G. Grande, T. V. Bui, and P. K. Rose Estimates of the Location of L-type Ca2+ Channels in Motoneurons of Different Sizes: A Computational Study J Neurophysiol, June 1, 2007; 97(6): 4023 - 4035. [Abstract] [Full Text] [PDF]

				A. T. Schaefer, M. Helmstaedter, A. C. Schmitt, D. Bar-Yehuda, M. Almog, H. Ben-Porat, B. Sakmann, and A. Korngreen Dendritic voltage-gated K+ conductance gradient in pyramidal neurones of neocortical layer 5B from rats J. Physiol., March 15, 2007; 579(3): 737 - 752. [Abstract] [Full Text] [PDF]

				M.-C. Perreault and M. Raastad Contribution of morphology and membrane resistance to integration of fast synaptic signals in two thalamic cell types J. Physiol., November 15, 2006; 577(1): 205 - 220. [Abstract] [Full Text] [PDF]

				A.-E. Tobin, S. D. Van Hooser, and R. L. Calabrese Creation and Reduction of a Morphologically Detailed Model of a Leech Heart Interneuron J Neurophysiol, October 1, 2006; 96(4): 2107 - 2120. [Abstract] [Full Text] [PDF]

				Y. Mao, B. Wang, and W. Kunze Characterization of Myenteric Sensory Neurons in the Mouse Small Intestine J Neurophysiol, September 1, 2006; 96(3): 998 - 1010. [Abstract] [Full Text] [PDF]

				T. V. Bui, M. Ter-Mikaelian, D. Bedrossian, and P. K. Rose Computational Estimation of the Distribution of L-type Ca2+ Channels in Motoneurons Based on Variable Threshold of Activation of Persistent Inward Currents J Neurophysiol, January 1, 2006; 95(1): 225 - 241. [Abstract] [Full Text] [PDF]

				S. M. ElBasiouny, D. J. Bennett, and V. K. Mushahwar Simulation of Dendritic CaV1.3 Channels in Cat Lumbar Motoneurons: Spatial Distribution J Neurophysiol, December 1, 2005; 94(6): 3961 - 3974. [Abstract] [Full Text] [PDF]

				N. L Golding, T. J Mickus, Y. Katz, W. L Kath, and N. Spruston Factors mediating powerful voltage attenuation along CA1 pyramidal neuron dendrites J. Physiol., October 1, 2005; 568(1): 69 - 82. [Abstract] [Full Text] [PDF]

				Y. Banitt, K. A. C. Martin, and I. Segev Depressed Responses of Facilitatory Synapses J Neurophysiol, July 1, 2005; 94(1): 865 - 870. [Abstract] [Full Text] [PDF]

				M. G. Maltenfort, C. A. Phillips, M. L. McCurdy, and T. M. Hamm Determination of the Location and Magnitude of Synaptic Conductance Changes in Spinal Motoneurons by Impedance Measurements J Neurophysiol, September 1, 2004; 92(3): 1400 - 1416. [Abstract] [Full Text] [PDF]

				M. G. Maltenfort, M. L. McCurdy, C. A. Phillips, V. V. Turkin, and T. M. Hamm Location and Magnitude of Conductance Changes Produced by Renshaw Recurrent Inhibition in Spinal Motoneurons J Neurophysiol, September 1, 2004; 92(3): 1417 - 1432. [Abstract] [Full Text] [PDF]

				M. G. Maltenfort and T. M. Hamm Estimation of the Electrical Parameters of Spinal Motoneurons Using Impedance Measurements J Neurophysiol, September 1, 2004; 92(3): 1433 - 1444. [Abstract] [Full Text] [PDF]

				T. V. Bui, S. Cushing, D. Dewey, R. E. Fyffe, and P. K. Rose Comparison of the Morphological and Electrotonic Properties of Renshaw Cells, Ia Inhibitory Interneurons, and Motoneurons in the Cat J Neurophysiol, November 1, 2003; 90(5): 2900 - 2918. [Abstract] [Full Text] [PDF]

				S. Hallermann, C. Pawlu, P. Jonas, and M. Heckmann A large pool of releasable vesicles in a cortical glutamatergic synapse PNAS, July 22, 2003; 100(15): 8975 - 8980. [Abstract] [Full Text] [PDF]

				A. T. Schaefer, M. Helmstaedter, B. Sakmann, and A. Korngreen Correction of Conductance Measurements in Non-Space-Clamped Structures: 1. Voltage-Gated K+ Channels Biophys. J., June 1, 2003; 84(6): 3508 - 3528. [Abstract] [Full Text] [PDF]

				J. Jamieson, H. D. Boyd, and E. M. McLachlan Simulations to Derive Membrane Resistivity in Three Phenotypes of Guinea Pig Sympathetic Postganglionic Neuron J Neurophysiol, May 1, 2003; 89(5): 2430 - 2440. [Abstract] [Full Text] [PDF]

				A. A. Prinz and P. Fromherz Effect of Neuritic Cables on Conductance Estimates for Remote Electrical Synapses J Neurophysiol, April 1, 2003; 89(4): 2215 - 2224. [Abstract] [Full Text] [PDF]

				C. C. McIntyre and W. M. Grill Extracellular Stimulation of Central Neurons: Influence of Stimulus Waveform and Frequency on Neuronal Output J Neurophysiol, October 1, 2002; 88(4): 1592 - 1604. [Abstract] [Full Text] [PDF]

				M.-C. Perreault Motoneurons Have Different Membrane Resistance during Fictive Scratching and Weight Support J. Neurosci., September 15, 2002; 22(18): 8259 - 8265. [Abstract] [Full Text] [PDF]

				K. A. Lindsay, J. M. Ogden, and J. R. Rosenberg Dendritic Subunits Determined by Dendritic Morphology Neural Comput., November 1, 2001; 13(11): 2465 - 2476. [Abstract] [Full Text]

				P. Vetter, A. Roth, and M. Hausser Propagation of Action Potentials in Dendrites Depends on Dendritic Morphology J Neurophysiol, February 1, 2001; 85(2): 926 - 937. [Abstract] [Full Text] [PDF]

				G. Svirskis, A. Gutman, and J. Hounsgaard Electrotonic Structure of Motoneurons in the Spinal Cord of the Turtle: Inferences for the Mechanisms of Bistability J Neurophysiol, January 1, 2001; 85(1): 391 - 398. [Abstract] [Full Text] [PDF]

				P. A. Nunez-Abades, J. M. Pattillo, T. M. Hodgson, and W. E. Cameron Role of Synaptic Inputs in Determining Input Resistance of Developing Brain Stem Motoneurons J Neurophysiol, November 1, 2000; 84(5): 2317 - 2329. [Abstract] [Full Text] [PDF]

				B. S. Mleux and L. E. Moore Active Dendritic Membrane Properties of Xenopus Larval Spinal Neurons Analyzed With a Whole Cell Soma Voltage Clamp J Neurophysiol, March 1, 2000; 83(3): 1381 - 1393. [Abstract] [Full Text] [PDF]

				R. K. Powers and M. D. Binder Summation of Effective Synaptic Currents and Firing Rate Modulation in Cat Spinal Motoneurons J Neurophysiol, January 1, 2000; 83(1): 483 - 500. [Abstract] [Full Text] [PDF]

				M. London, C. Meunier, and I. Segev Signal Transfer in Passive Dendrites with Nonuniform Membrane Conductance J. Neurosci., October 1, 1999; 19(19): 8219 - 8233. [Abstract] [Full Text] [PDF]

				A. Surkis, C. S. Peskin, D. Tranchina, and C. S. Leonard Recovery of Cable Properties Through Active and Passive Modeling of Subthreshold Membrane Responses From Laterodorsal Tegmental Neurons J Neurophysiol, November 1, 1998; 80(5): 2593 - 2607. [Abstract] [Full Text] [PDF]

				G. Stuart and N. Spruston Determinants of Voltage Attenuation in Neocortical Pyramidal Neuron Dendrites J. Neurosci., May 15, 1998; 18(10): 3501 - 3510. [Abstract] [Full Text] [PDF]

				D. Thurbon, H.-R. Luscher, T. Hofstetter, and S. J. Redman Passive Electrical Properties of Ventral Horn Neurons in Rat Spinal Cord Slices J Neurophysiol, May 1, 1998; 79(5): 2485 - 2502. [Abstract] [Full Text] [PDF]

				G. Svirskis, A. Gutman, and J. Hounsgaard Detection of a Membrane Shunt by DC Field Polarization During Intracellular and Whole Cell Recording J Neurophysiol, February 1, 1997; 77(2): 579 - 586. [Abstract] [Full Text] [PDF]

				K. E. Jones and P. Bawa Computer Simulation of the Responses of Human Motoneurons to Composite 1A EPSPS: Effects of Background Firing Rate J Neurophysiol, January 1, 1997; 77(1): 405 - 420. [Abstract] [Full Text] [PDF]

				M. Gonzalez and W. F. Collins III Modulation of Motoneuron Excitability by Brain-Derived Neurotrophic Factor J Neurophysiol, January 1, 1997; 77(1): 502 - 506. [Abstract] [Full Text] [PDF]