Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Cortically and lingually induced postsynaptic potentials in trigeminal motoneurons after axotomy

  • 21 Accesses

  • 4 Citations

Summary

The membrane properties and the efficacy of excitatory and inhibitory synapses were studied in cat masseteric motoneurons (Mass Mns) after axotomy. In axotomized Mass Mns the slope of the primary range in the frequency-current relationship showed a higher gain than that of normal Mass Mns. The safety of antidromic invasion was increased and the initial segment component of antidromic action potentials could not be separated from the somadendritic component. In normal Mass Mns a single shock delivered to the orbital gyrus or the lingual nerve induced long-lasting inhibitory postsynaptic potentials (IPSPs). In two-thirds of Mass Mns explored 30 days after axotomy, a single shock delivered to the orbital gyrus or the lingual nerve evoked a mixture of inhibitory and excitatory synaptic potentials. In Mass Mns 50 days after axotomy, we have demonstrated that the major fraction of the total sample of explored Mass Mns showed long-lasting excitatory postsynaptic potentials followed by IPSPs. The results suggest that in Mass Mns, axotomy is followed by the decline of synaptic efficacy of inhibitory rather than of excitatory synapses.

This is a preview of subscription content, log in to check access.

References

  1. Baldissera F, Gustafsson B (1974) Firing behaviour of a neuron model based on the afterhyperpolarization conductance time course and algebraical summation. Adaptation and steady state firing. Acta Physiol Scand 92: 27–47

  2. Burke RE, Walmsley B, Hodgson JA (1979) HRP anatomy of group Ia afferent contacts on alpha motoneurons. Brain Res 160: 347–352

  3. Calvin WH (1974) Three modes of repetitive firing and the role of threshold time course between spikes. Brain Res 69: 341–346

  4. Eccles JC, Libet B, Young RR (1958) The behaviour of chromatolysed motoneurones studied by intracellular recording. J Physiol (Lond) 143: 11–40

  5. Engberg I, Marshall IC (1979) Reversal potential for Ia excitatory post synaptic potentials in spinal motoneurones of cats. Neuroscience 4: 1583–1591

  6. Gallego R, Kuno M, Nuñez R, Snider WD (1979) Disuse enhances synaptic efficacy in spinal motoneurones. J Physiol (Lond) 291: 191–205

  7. Gallego R, Kuno M, Nuñez R, Snider WD (1980) Enhancement of synaptic function in cat motoneurones during peripheral sensory regeneration. J Physiol (Lond) 306: 205–218

  8. Goldberg LJ (1972) Excitatory and inhibitory effects of lingual nerve stimulation on reflexes controlling the activity of masseteric motoneurons. Brain Res 39: 95–108

  9. Gustafsson B (1979) Changes in motoneurone electrical properties following axotomy. J Physiol (Lond) 293: 197–215

  10. Heyer CB, Llinás R (1977) Control of rhythmic firing in normal and axotomized cat spinal motoneurons. J Neurophysiol 40: 480–488

  11. Jack JJB, Miller S, Porter R, Redman SJ (1971) The time course of minimal excitatory postsynaptic potentials evoked in spinal motoneurones by group Ia afferent fibers. J Physiol (Lond) 215: 353–380

  12. Kernell D (1965) The adaptation and the relation between discharge frequency and current strength of cat lumbosacral motoneurones stimulated by long-lasting injected currents. Acta Physiol Scand 65: 65–73

  13. Kidokoro Y, Kubota K, Shuto S, Sumino R (1968) Reflex organization of cat masticatory muscles. J Neurophysiol 31: 695–708

  14. Kubo Y, Emoto S, Nakamura Y (1981) Synaptic basis of orbital cortically induced rhythmical masticatory activity of trigeminal motoneurons in immobilized cats. Brain Res 230: 97–110

  15. Kuno M, Llinás R (1970a) Enhancement of synaptic transmission by dendritic potentials in chromatolysed motoneurones of the cat. J Physiol (Lond) 210: 807–821

  16. Kuno M, Llinás R (1970b) Alterations of synaptic action in chromatolysed motoneurones of the cat. J Physiol (Lond) 210: 823–838

  17. Nakamura Y, Goldberg LJ, Clemente CD (1967) Nature of suppression of the masseteric monosynaptic reflex induced by stimulation of the orbital gyrus of the cat. Brain Res 6: 184–198

  18. Nelson SG, Collatos TC, Niechaj A, Mendell LM (1979) Immediate increase in Ia-motoneuron synaptic transmission caudal to spinal cord transection. J Neurophysiol 42: 655–664

  19. Nelson SG, Mendell LM (1979) Enhancement in Ia-motoneuron synaptic transmission caudal to chronic spinal cord transection. J Neurophysiol 42: 642–654

  20. Rall W (1967) Distinguishing theoretical synaptic potentials for different soma-dendritic distributions of synaptic input. J Neurophysiol 30: 1138–1168

  21. Rall W, Burke RE, Smith TG, Nelson PG, Frank K (1967) Dendritic location of synapses and possible mechanisms for the monosynaptic EPSP in motoneurons. J Neurophysiol 30: 1169–1193

  22. Rotter A, Birdsall NJM, Burgen ASV, Field PM, Smolen A, Raisman G (1979) Muscarinic receptors in the central nervous system of the rat. IV. A comparison of the effects of axotomy and deafferentation on the binding of [3H] propylbenzilylcholine mustard and associated synaptic changes in the hypoglossal and pontine nuclei. Brain Res Rev 1: 207–224

  23. Smith TG, Wuerker RB, Frank K (1967) Membrane impedance changes during synaptic transmission in cat spinal motoneurons. J Neurophysiol 30: 1072–1096

  24. Sumner BEH (1975a) A quantitative analysis of the responses of presynaptic boutons to postsynaptic motor neuron axotomy. Exp Neurol 46: 605–615

  25. Sumner BEH (1975b) A quantitative analysis of boutons with different types of synapse in normal and injured hypoglossal nuclei. Exp Neurol 49: 406–417

  26. Sumner BEH (1975c) A quantitative study of subsurface cisterns and their relationships in normal and axotomized hypoglossal neurones. Exp Brain Res 22: 175–183

  27. Sumner BEH, Sutherland FI (1973) Quantitative electron microscopy on the injured hypoglossal nucleus in the rat. J Neurocytol 2: 315–328

  28. Takata M (1980a) Synaptic linkage of masseter muscle afferents to masseteric motoneurones in the cat. Neuroscience 5: 1429–1436

  29. Takata M (1980b) Neutral circuit for the jaw-opening reflex. In: Kubota K, Nakamura Y, Schumacher GH (eds) Jaw position and jaw movement. VEB Verlag Volk und Gesundheit, Berlin, pp 248–259

  30. Takata M (1981) Lingually induced inhibitory postsynaptic potentials in hypoglossal motoneurons after axotomy. Brain Res 224: 165–169

  31. Takata M, Fujita S (1979) The properties of lingually induced IPSPs in the masseteric motoneurons. Brain Res 168: 648–651

  32. Takata M, Fujita S (1982) The properties of excitatory postsynaptic potentials evoked in trigeminal motoneurons by trigeminal nerve stimulation. Brain Res 241: 171–175

  33. Takata M, Fujita S, Kanamori N (1982) Repetitive firing in trigeminal mesencephalic tract neurons and trigeminal motoneurons. J Neurophysiol 47: 23–30

  34. Takata M, Nagahama T (1983) Synaptic efficacy of inhibitory synapses in hypoglossal motoneurons after transection of the hypoglossal nerve. Neuroscience 10: 23–29

  35. Takata M, Shohara E, Fujita S (1980) The excitability of hypoglossal motoneurons undergoing chromatolysis. Neuroscience 5: 413–419

Download references

Author information

Correspondence to M. Takata.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Takata, M., Nagahama, T. Cortically and lingually induced postsynaptic potentials in trigeminal motoneurons after axotomy. Exp Brain Res 61, 272–279 (1986). https://doi.org/10.1007/BF00239517

Download citation

Key words

  • Membrane property
  • Postsynaptic potentials
  • Axotomized trigeminal motoneuron
  • Cat