TRH and Substance P Increase Rat Motoneurone Excitability through a Block of a Novel K+ Conductance
Immunocytochemical studies of the fine localization of endogenously-occurring TRH and substance P in the mammalian spinal cord have shown that these two peptides are present in the terminals of fibres descending from the raphe nucleus and which establish synaptic contacts with the proximal dendrites of motoneurons.1,7. Other nerve cells containing these peptides are found in the spinal dorsal horn.
KeywordsReversal Potential Input Resistance Spinal Dorsal Horn Current Clamp Tachykinin Receptor
Unable to display preview. Download preview PDF.
- 1.Arvidsson, U., Cullheim, S., Ulfhake, B., Bennett, G.W., Fone, K.C.F., Cuello, A.C., Verhofstad, A.A.J., Visser, T.J. and Hökfelt, T. (1990) 5-Hydroxytryptamine, substance P, and thyrotropin-releasing hormone in the adult cat spinal cord segment L7:immunohistochemical and chemical studies. Synapse 6, 237–270.PubMedCrossRefGoogle Scholar
- 4.Fisher, N.D. and Nistri, A. (1993) Substance P and TRH share a common effector pathway in rat spinal motoneurons: an in vitro electrophysiological study. Neurosci. Lett, (in press).Google Scholar
- 7.Johanssen, O., Hökfelt, T., Jeffcoate, S.L., White, N. and Sternberger, L.A. (1980) Ultrastructural localization of TRH-like immunoreactivity. Exp. Brain Res. 38, 1–10.Google Scholar
- 8.Maggi, C.A., Patacchini, R., Rovero, P. and Giachetti, A. (1993) Tachykinin receptors and tachykinin receptor antagonists. J. Auton. Pharmacol. 13, (in press).Google Scholar
- 13.Sharif, N.A. and Burt, D.R. (1985) Limbic, hypothalamic, cortical and spinal regions are enriched in receptors for thyrotropin-releasing hormone: evidence from [3H] ultrafilm autoradiography and correlation with central effects of the tripeptide in rat brain. Neurosci. Lett. 60, 337–342.PubMedCrossRefGoogle Scholar