Glutamate-immunoreactivity in the trigeminal and dorsal root ganglia, and intraspinal neurons and fibres in the dorsal horn of the rat
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.Get Access
Putative aspartergic and glutamatergic sensory neurons in the rat were identified by autoradiography and immunocytochemistry respectively. Approximately 3% of large L4 dorsal root ganglion neurons (diameter 18–52 μm) accumulated radiolabelled aspartate, whereas all satellite glia had high affinity for the amino acid. Glutamate-immunofluorescent (Glu-FITC) dorsal root ganglia neurons comprised 38.3% at S1, 35.6% at L2 33.9% at C5 and 28.8% at T6. Numbers of immunoreactive neurons were higher with the more sensitive peroxidase-anti-peroxidase (Glu-PAP) method; and the cell counts totalled 42% (S1), 41.2% (L4), 35% (C5) and 34.6% (T6). The trigeminal ganglion (TG) contained 24% Glu-FITC and 32.3% Glu-PAP positive cells. The majority of glutamate-immunoreactive sensory neurons were small, ranging from 10–35 μm with median diameters of 17.5μm (C5), 21μm (S1), 24.2μm (TG) and 28.5 μm (L2). It is evident therefore, that a subgroup of class B cells are glutamatergic. Glutamate immunoreactivity in the spinal cord was similar in all segments and was localized in the superficial lamina and substantia gelatinosa of the dorsal horn. Stained interneurons were located among the immunoreactive fibres. The dorsolateral funiculus contained dense plexus of immunoreactive fibres which increased in prominence after intraperitoneal injection of L-glutamate, but penetration of exogenous glutamate into the grey matter was limited. Instead, the meninges and basal layers of the spinal blood vessels were intensely immunoreactive. The studies describe the subtypes of acidic amino acidergic neurons and relates the immunohistochemistry to a functional subclass.
- Barbaresi, P., Rustioni, A. &Cuenod, M. (1985) Retrograde labelling of dorsal root ganglion neurons after injection of tritiated amino acid in the spinal cord of rats and cats.Somatosen. Res. 3, 57–74.
- Cangro, C. B., Sweetnam, P. M., Wrathall, J. R., Haser, W. B., Curthoys, N. P. &Neale, J. H. (1985) Localisation of elevated glutaminase immunoreactivity in small DRG neurons.Brain Res.,336, 158–61.
- Duce, I. R. &Keen, P. (1983) Selective uptake of [3H] glutamine and [3H] glutamate into neurons and satellite cells of dorsal root gangliain vitro.Neurosci. 8 (4), 861–6.
- Hunt, S. P. (1983) Cytochemistry of the spinal cord. InChemical Neuroanatomy (edited byEmson, P. C.) pp. 53–4. New York: Raven Press.
- Jessell, T. M., Yoshika, K. &Jahr, C. E. (1986) Amino acid receptor mediated transmission of primary afferent synapses in rat spinal cord.J. Exp. Biol. 124, 239–59.
- Johnson, J. L. (1977) Glumatic acid as a synaptic transmitter candidate in the dorsal sensory neuron: Reconsiderations.Life Sci. 20, 1637–44.
- Jones, I. M., Jordan, C. C., Morton, I. K. M., Stagg, C. J. &Webster, R. A. (1974) The effect of chronic dorsal root section on the concentration of free amino acids in the rabbit spinal cord.J. Neurochem. 23, 1239–44.
- Lawson, S. N. (1979) The postnatal development of large light and small dark neurons in mouse dorsal root ganglia: a statistical analysis of cell numbers and size.J. Neurocytol. 8, 275–94.
- Magnusson, K. R., Beitz, A., Larson, A. A., Madl, J. E. &Altschuler, R. A. (1985) Immunohistochemical localization of glutamate, glutaminase and aspartyl aminotransferase neurons in the spinal trigeminal nucleus of the rat.Proc. Soc. Neurosci. 11, 579.
- Rambourg, A., Clermont, Y. &Beaudet, A. (1983) Ultrastructural features of six types of neurons in rat dorsal root ganglia.J. Neurocytol. 12, 47–66.
- Rustioni, A. &Weinberg, R. J. (1989) The somatosensory system. InHandbook of Chemical Neuroanatomy 7 (edited byA. Bjorklund, T. Kokfelt &L. W. Swanson) pp. 219–30 Elsevier, Amsterdam, NY, Oxford.
- Salt, T. E. &Hill, R. G. (1983) Neurotransmitter candidates of somatosensory primary afferent fibres.Neurosc. 10, 1083–103.
- Schon, F. &Kelly, J. S. (1974) Autoradiographic localization of [3H]GABA and [3H]glutamate over satellite glial cells.Brain Res. 66, 275–88.
- Sequela, P. H., Buif, R. D. &Le Moal, M. (1984) Antibodies against Y-aminobutyric acid. Specificity studies and immunocytochemical studies.Proc Natl. Acad. Sci. 81, 3888–92.
- Takeuchi, Y., Kojima, M., Matsura, T. &Sano, Y. (1983) Serotoninergic innervation on the motorneurons in the mammalian brainstem.Anat. Embryol. 167, 320–33.
- Tuchscherer, M. M. &Seybold V. S. (1985) Immunohistochemical studies of substance P, cholecystokininoctopeptide and somatostatin in dorsal root ganglia of the rat.Neurosci. 14(2), 593–605.
- Wanaka, A., Shiotani, Y., Kiyama, H., Matsuyama, T. Kamada, T., Shiosaka, S. &Tohyama, M. (1987) Glutamate-like immunoreactivity structures in primary sensory neurons in the rat detected by a specific antiserum against glutamate.Exp. Brain Res. 65, 691–4.
- Weinberg, R., Conti, J. F., Van Eyck, S. L., Petruz, P. &Rustioni, A., (1987) Glutamate immunoreactivity in superficial laminae of rat dorsal horn and spinal trigeminal nucleus.InExcitatory amino acid transmission (edited byT. P. Hicks, D. Lodge &H. McLennan). pp. 173–6, Alan R. Liss, New York.
- Westlund, K. N., McNeill, L., Coggeshall, R. E. (1989a) Glutamate immunoreactivity in rat dorsal root axons.Neurosci. Letts. 96, 13–17.
- Westlund, K. N., McNeill, D. L., Patterson, J. T. &Coggershall, R. E. (1989b) Aspartate immunoreactive axons in normal rat L4 dorsal roots.Brain Res. 489, 347–57.
- Glutamate-immunoreactivity in the trigeminal and dorsal root ganglia, and intraspinal neurons and fibres in the dorsal horn of the rat
The Histochemical Journal
Volume 23, Issue 4 , pp 171-179
- Cover Date
- Print ISSN
- Online ISSN
- Kluwer Academic Publishers
- Additional Links
- Industry Sectors