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The Detailed Morphology of the Cortical Terminals of the Thalamocortical Fibres from the Ventromedial Nucleus in the Rat

  • G. W. Arbuthnott
  • N. K. MacLeod
  • D. J. Maxwell
  • A. K. Wright
Part of the Advances in Behavioral Biology book series (ABBI, volume 32)

Abstract

Iontophoretic injections of the Phaseolus Vulgaris leucoagglutinin (PhAL) in the region of the ventromedial thalamic nucleus of the rat resulted in a complete “Golgi-like” filling of small groups of neurones. The gross distribution of the terminals across the surface of the cortex confirms earlier studies with other tracing methods. The detail available in the PhAL material suggests a rather more restricted domain of influence for individual cells. Some terminal axons were limited to a small area in the motor cortex with boutons in both deeper and surface layers. Other terminals ran for several millimeters, parallel to the surface and immediately below it. In related electrophysiological experiments two groups of ventromedial cells were encountered. One group was antidromically activated by threshold stimulation only in a small area of cortex. Another was characterised by activation from several points on the cortical surface along a strip with a maximum width of 0.5mm but which could be as long as the exposed area of cortex.

Keywords

Cortical Surface Cortical Stimulation Ventromedial Nucleus Camera Lucida Drawing Iontophoretic Injection 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Anderson, P., Eccles, J. C. and Sears, T. A., 1964, The ventro-basal complex of the thalamus: types of cells, their responses and their functional organization, J. Physiol 174: 370–399.Google Scholar
  2. Arbuthnott, G. W. and Wright, A. K., 1982, Some non-fluorescent connections of the nigro-neostriatal dopamine neurones, Brain Research Bull. 9: 367–378.CrossRefGoogle Scholar
  3. Dempsey, E. W., and Morrison, R. S., 1942, The interaction of certain spontaneous and induced cortical potentials, J. Physiol. 135: 301–308.Google Scholar
  4. DiChiara, G., Morelli, M., Porceddu, M. L., and Gessa, G. L., 1979a, Role of thalamic γ-aminobutyrate in motor functions: catalepsy and ipsiversive turning after intrathalamic muscimol, Neuroscience 4: 1453–1465.CrossRefGoogle Scholar
  5. DiChiara, G., Proceddu, M. L., Morelli, M., Mulas, M. L., and Gessa, G.C., 1979b, Substantia nigra as an output station for striatal dopaminergic responses: role of GABA-mediated inhibition of pars reticulata neurons, Naunyn-Schmeid. Arch. Pharmac. 306: 153–159.CrossRefGoogle Scholar
  6. Divac, I., Kosmal, A., Bjorklund, A. and Lindvall, O., 1978, Subcortical projections to the prefrontal cortex in the rat as revealed by the horseradish peroxidase technique, Neuroscience 3: 785–796.PubMedCrossRefGoogle Scholar
  7. Garcia-Munoz, M., Patino, P., Wright, A. K., and Arbuthnott, G. W., 1983, The anatomical substrate of the turning behaviour seen after lesions in the nigrostriatal dopamine system, Neuroscience 8: 87–95.PubMedCrossRefGoogle Scholar
  8. Glenn, L. L., Hada, J., Roy, J. P., Deschenes, M., and Steriade, M., 1982, Anterograde tracer and field potential analysis of the neocortical layer 1 projection from nucleus ventral is medial is of the thalamus in cat, Neuroscience 7: 1861–1877.PubMedCrossRefGoogle Scholar
  9. Herkenham, M., 1979, The afferent and efferent connections of the ventromedial thalamic nucleus in the rat, J. Comp. Neurol. 183: 487–518.PubMedCrossRefGoogle Scholar
  10. Leigh, P. N., Reavill, C., Jenner, P., and Marsden, C. D., (1983), Basal Ganglia outflow pathways and circling behaviour in the rat, J. Neural Transm. 58: 1–41.PubMedCrossRefGoogle Scholar
  11. MacLeod, N. K., and James, T. A., 1984, Regulation of cerebellocortical transmission in the rat ventromedial thalamic nucleus, Exp. Br. Res. 55: 535–552.Google Scholar
  12. Maxwell, D. J., Bannatyne, B. A., Fyffe, R. E. W., and Brown, A. G., 1984, Fine structure of primary afferent axon terminals projecting from rapidly adapting mechanoreceptors of the toe and foot pads of the cat, Q.J. Exp. Physiol, 69: 381–392.PubMedGoogle Scholar
  13. Paxinos, G., and Watson, C., 1982, “The Rat Brain in stereotoxic co-ordinates”, Academic Press, Sydney.Google Scholar
  14. Somogyi, P. and Takagi, H., 1982, A note on the use of picric acidparaformaldehyde-glutaraldehyde fixative for correlated light and electron microscopical immunocytochemistry, Neuroscience, 7: 1779–1783.PubMedCrossRefGoogle Scholar
  15. Zilles, I.C. 1985,“The Cortex of the Rat” Springer-Verlag, Berlin.CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • G. W. Arbuthnott
    • 1
    • 2
  • N. K. MacLeod
    • 1
    • 2
  • D. J. Maxwell
    • 1
    • 2
  • A. K. Wright
    • 1
    • 2
  1. 1.MRC Brain Metabolism Unit and Department of PhysiologyUniversity of EdinburghEdinburghScotland
  2. 2.Department of Preclinical Veterinary SciencesThe Royal (Dick) School of Veterinary StudiesEdinburghScotland

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