Abstract
An introductory survey is given of the cellular physiology of motoneurones (MNs). Steady driving currents, applied to individual cells through microelectrodes, may be used for determining such key parameters as the range of possible discharge rates and the shape and steepness of the curve relating discharge frequency to current intensity (f-I relation). Quantitatively, MN properties may vary considerably between animal species and between cells innervating different types of muscle fibres. Central synapses impinging upon MNs often simply provide “driving” currents, altering MN discharge rate largely in accordance with the f-I relation. In addition, metabotropic synapses may have “MN-modifying” effects, altering MN membrane and activation properties in various ways. Studies of MN firing and response patterns in normal and pathological motor behaviour is essential for evaluating the functional role of short-and long-term modifications of MN properties.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
Bennett, D. J., Hultborn, H., Fedirchuk, B., and Gorassini, M., 1998, Synaptic activation of plateaus in hindlimb motoneurons of decerebrate catsJournal of Neurophysiology80, 2023–2037.
Berger, A. J., Bayliss, D. A., and Viana, F., 1996, Development of hypoglossal motoneuronsJournal of Applied Physiology81, 1039–1048.
Binder, M. D., Heckman, C. J., and Powers, R. K., 1996, The physiological control of motoneuron activity, in:Handbook of Physiology. Exercise. Regulation and Integration of Multiple SystemsAmerican Physiological Society, New York, pp. 3–53.
Carlin, K. P., Jones, K. E., Jiang, Z., Jordan, L. M., and Brownstone, R. M., 2000, Dendritic L-type calcium currents in mouse spinal motoneurons: implications for bistabilityEuropean Journal of Neuroscience12, 1635–1646.
Conway, B. A., Hultborn, H., Kiehn, O., and Mintz, I., 1988, Plateau potentials in alpha-motoneurones induced by intravenous injection of L-dopa and clonidine in the spinal catJournal of Physiology405, 369–384.
Copray, S., and Kemell, D., 2000, Neurotrophins and trk-receptors in adult rat spinal motoneurons: differences related to cell size but not to ‘slow/fast’ specialization,.NeuroscienceLetters289, 217–220.
Czeh, G., Gallego, R., Kudo, N., and Kuno, M., 1978, Evidence for the maintenance of motoneurone properties by muscle activityJournal of Physiology281, 239–252.
Delgado-Lezama, R., and Hounsgaard, J., 1999, Adapting rnotoneurons for motor behaviorProgress in Brain Research123, 57–63.
Delgado-Lezama, R., Perrier, J. F., and Hounsgaard, J., 1999, Local facilitation of plateau potentials in dendrites of turtle motoneurones by synaptic activation of metabotropic receptorsJournal of Physiology515,203–207.
Foehring, R. C., Sypert, G. W., and Munson, J. B., 1987, Motor-unit properties following cross-reinnervation of cat lateral gastrocnemius and soleus muscles with medial gastrocnemius nerve. II. Influence of muscle on motoneuronsJournal of Neurophysiology57, 1227–1245.
Gao, B. X., and Ziskind-Conhaim, L., 1998, Development of ionic currents underlying changes in action potential waveforms in rat spinal motoneuronsJournal of Neurophysiology80, 3047–3061.
Gardiner, P. F., and Kernell, D., 1990, The fastness of rat motoneurones: time course of afterhyperpolarization in relation to axonal conduction velocity and muscle unit contractile speedPflügers Archives415, 762–766.
Gonzalez, M., and Collins, W. F., 3rd, 1997, Modulation of motoneuron excitability by brain-derived neurotrophic factorJournal of Neurophysiology77, 502–506.
Granit, R., Kemell, D., and Lamarre, Y., 1966, Algebraical summation in synaptic activation of motoneurones firing within the ‘primary range’ to injected currentsJournal of Physiology187, 379–399.
Heckman, C. J., and Lee, R. H., 1999, Synaptic integration in bistable motoneuronsProgress in Brain Research123, 49–56.
Heyer, C. B., and Llinas, R., 1977, Control of rhythmic firing in normal and axotomized cat spinal motoneuronsJournal of Neurophysiology40, 480–488.
Hounsgaard, J., Hultbom, H., Jespersen, B., and Kiehn, O., 1988, Bistability of ‘alpha’-motoneurones in the decerebrate cat and in the acute spinal cat after intravenous 5-hydroxytryptophanJournal of Physiology405, 345–367.
Hounsgaard, J., and Kiehn, O., 1989, Serotonin-induced bistability of turtle motoneurones caused by a nifedipine-sensitive calcium plateau potentialJournal of Physiology414, 265–282.
Hultbom, H., 1999, Plateau potentials and their role in regulating motoneuronal firingProgress in Brain Research123, 39–48.
Jiang, Z., Rempel, J., Li, J., Sawchuk, M. A., Carlin, K. P., and Brownstone, R. M., 1999, Development of L-type calcium channels and a nifedipine-sensitive motor activity in the postnatal mouse spinal cordEuropean Journal of Neuroscience 113481–3487.
Kernell, D., 1969, Synaptic conductance changes and the repetitive impulse discharge of spinal motoneuronesBrain Research15, 291–294.
Kemell, D., 1992, Organized variability in the neuromuscular system: A survey of task-related adaptationsArchives Italiennes de Biologie 13019–66.
Kiehn, O., Erdal, J., Eken, T., and Bruhn, T., 1996, Selective depletion of spinal monoamines changes the rat coleus EMG from a tonic to a more phasic patternJournal of Physiology492, 173–184.
Lee, R. H., and Heckman, C. J., 1998, Bistability in spinal motoneurons in vivo: systematic variations in rhythmic firing patternsJournal of Neurophysiology80, 572–582.
Lee, R. H., and Heckman, C. J., 2000, Adjustable amplification of synaptic input in the dendrites of spinal motoneurons in vivoJournal of Neuroscience20, 6734–6740.
Lee, R. H., and Heckman, C. J., 2001, Essential role of a fast persistent inward current in action potential initiation and control of rhythmic firingJournal of Neurophysiology85, 472–475.
Martin-Caraballo, M., and Greer, J. J., 1999, Electrophysiological properties of rat phrenic motoneurons during perinatal developmentJournal of Neurophysiology81, 1365–1378.
Matthews, P. B., 1996, Relationship of firing intervals of human motor units to the trajectory of post-spike after-hyperpolarization and synaptic noiseJournal of Physiology492, 597–628.
Munson, J. B., Foehring, R. C., Mendell, L. M., and Gordon, T., 1997, Fast-to-slow conversion following chronic low-frequency activation of medial gastrocnemius muscle in cats. II. Motoneuron propertiesJournal of Neurophysiology77, 2605–2615.
Perrier, J. F., Noraberg, J., Simon, M., and Hounsgaard, J., 2000, Dedifferentiation of intrinsic response properties of motoneurons in organotypic cultures of the spinal cord of the adult turtleEuropean Journal of Neuroscience12, 2397–2404.
Piotrkiewicz, M., Hausmanowa-Petrusewicz, L., and Mierzejewska, J., 1999, Motoneurons are altered in muscular dystrophyJournal de Physiologie93, 167–173.
Powers, R. K., and Binder, M. D., 1995, Effective synaptic current and motoneuron firing rate modulationJournal of Neurophysiology74, 793–801.
Powers, R. K., and Binder, M. D., 2000a, Relationship between the time course of the afterhyperpolarization and discharge variability in cat spinal motoneuronesJournal of Physiology528, 131–150.
Powers, R. K., and Binder, M. D., 2000b, Summation of effective synaptic currents and firing rate modulation in cat spinal motoneuronsJournal of Neurophysiology83, 483–500.
Powers, R. K., and Binder, M. D., 2001, Input-output functions of mammalian motoneuronsReviews in Physiology Biochemistry and Pharmacology143, 137–263.
Schwindt, P. C., and Crill, W. E., 1980, Properties of a persistent inward current in normal and TEA-injected motoneuronsJournal of Neurophysiology43, 1700–1724.
Van Dongen, P. A., Grillner, S., and Hokfelt, T., 1986, 5-Hydroxytryptamine (serotonin) causes a reduction in the afterhyperpolarization following the action potential in lamprey motoneurons and premotor intemeuronsBrain Research366, 320–325.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2002 Springer Science+Business Media New York
About this chapter
Cite this chapter
Kernell, D. (2002). Things We Know and Do Not Know About Motoneurones. In: Gandevia, S.C., Proske, U., Stuart, D.G. (eds) Sensorimotor Control of Movement and Posture. Advances in Experimental Medicine and Biology, vol 508. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-0713-0_22
Download citation
DOI: https://doi.org/10.1007/978-1-4615-0713-0_22
Publisher Name: Springer, Boston, MA
Print ISBN: 978-1-4613-5206-8
Online ISBN: 978-1-4615-0713-0
eBook Packages: Springer Book Archive