Neurophysiology

, Volume 21, Issue 3, pp 254–258 | Cite as

Tryptamine as an endogenous modulator of neuronal sensitivity to serotonin

  • I. V. Komissarov
  • I. I. Abramets
  • I. M. Samoilovich
Article
Received:

Abstract

Research was performed on sensory ganglia isolated from adult rats using intracellular techniques for recording membrane potential and by measuring resistance at the membrane of individual units. It was found that tryptamine at high concentrations manifests serotoninlike activity, but, at concentrations not affecting potential and resistance at the neuronal membrane, either reinforces (at a concentration of 10−7 M) or attenuates (at 10−5 M) serotonin (5-HT) effects mediated by type 1A (but not type 2) 5-HT receptors. 5-HT-modulated effects were produced by tryptamine-induced changes in 5-HT sensitivity at the neuronal membrane and remained unchanged by maximum level of this transmitter. Harmane acts similarly to tryptamine, although harmane derivatives (C-412 and C-506 respectively) produce either potentiation or inhibition of 5-HT1A over the entire concentration range used (of 10–7 M-10–5 M). The allosteric nature of 5-HT-modulation by tryptamine and harmane is discussed.

Keywords

Serotonin Membrane Potential Maximum Level Tryptamine Neuronal Membrane 
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.
This is a preview of subscription content, log in to check access.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Literature cited

  1. 1.
    I. I. Abramets, I. V. Komissarov, and I. M. Samoilovich, "Metabolic and ionic dependence of serotonin-induced neuronal response in rat sensory ganglia," Neirofiziologiya,21, No. 1, 86–93 (1989).Google Scholar
  2. 2.
    I. V. Komissarov, Mechanisms Underlying Chemical Sensitivity of Synaptic Membranes [in Russian], Nauk. Dumka, Kiev (1986).Google Scholar
  3. 3.
    V. K. Rudzit, Tryptophan [in Russian], Meditsina, Moscow (1973).Google Scholar
  4. 4.
    L. K. Ryago, A. M. Nurk, A. Ya. Korneev, and L. Kh. Allikmets, "Binding between phenibut and bicuculline-insensitive GABA receptors in the rat brain," Byull. Eksp. Biol. Med.,94, No. 11, 58–59 (1982).Google Scholar
  5. 5.
    M. M. Airaksinen, A. Lecklin, V. Saano, et al., "Tremorogenic effect and inhibition of tryptamine and serotonin receptor binding by beta-carbolines," Pharmacol. Toxicol.,60, No. 1, 5–8 (1987).PubMedGoogle Scholar
  6. 6.
    G. Bruning and H. Rommelspacher, "High affinity3H-tryptamine binding sites in various organs of the rat," Life Sci.,34, No. 15, 1441–1446 (1984).PubMedGoogle Scholar
  7. 7.
    C. S. Cascio and K. J. Kellar, "Characterization of3H-tryptamine binding sites in brain," Eur. J. Pharmacol.,95, No. 1, 31–39 (1983).PubMedGoogle Scholar
  8. 8.
    B. V. Cleineschmidt and V. J. Lotti, "Indolamine antagonists: relative potentials as inhibitors of tryptamine and 5-hydroxytryptophane-evoked responses," Br. J. Pharmacol.,50, No. 2, 311–313 (1974).PubMedGoogle Scholar
  9. 9.
    G. Curzon and C. A. Marsden, "Role of tryptamine in the behavioural changes caused by a monoamine oxidase inhibitor and L-tryptophan," Br. J. Pharmacol.,60, No. 2, 307–308 (1977).Google Scholar
  10. 10.
    D. Eccleston, G. W. Ashcroft, T. B. Crawford, and R. Loose, "Some observation on the estimation of tryptamine in tissues," J. Neurochem.,13, No. 2, 93–101 (1966).PubMedGoogle Scholar
  11. 11.
    F. J. Ehlert, "Inverse agonists", cooperativity and drug action at benzodiazepine receptors," Trends Pharmacol. Sci.,7, No. 1, 28–32 (1986).Google Scholar
  12. 12.
    K. H. Ginzel and S. R. Kottegoda, "A study of the vascular action of 5-hydroxytryptamine, tryptamine, adrenaline and noradrenaline," J. Exp. Physiol.,38, No. 3, 225–231 (1953).Google Scholar
  13. 13.
    A. S. Horn and S. R. Snodgrass, "The occurrence of tryptamine in rat brain and its pharmacological manipulation," Br. J. Pharmacol.,47, No. 3, 646 (1973).Google Scholar
  14. 14.
    R. S. G. Jones, "In vivo pharmacological studies on the interactions between tryptamine and 5-hydroxytryptamine," Br. J. Pharmacol.,73, No. 2, 485–493 (1981).PubMedGoogle Scholar
  15. 15.
    R. S. G. Jones, "Responses of cortical neurones to stimulation of the nucleus raphe medianu medianus: a pharmacological analysis of the role of indolamines," Neuropharmacology,21, No. 6, 511–520 (1982).PubMedGoogle Scholar
  16. 16.
    K. J. Kellar and C. S. Cascio, "3H-tryptamine: high affinity binding sites in rat brain," Eur. J. Pharmacol.,78, No. 4, 475–478 (1982).PubMedGoogle Scholar
  17. 17.
    R. A. North, J. T. Williams, A. Surprenant, and M. J. Christie, "μ and δ receptors belong to a family of receptors that are coupled to potassium channels," Proc. Natl. Acad. Sci., USA,81, No. 15, 5487–5491 (1987).Google Scholar
  18. 18.
    M. J. Raleigh, "Differential behavioral effects of tryptophan and 5-hydroxytryptamine in vervet monkeys: influence of catecholaminergic systems," Psychopharmacology,93, No. 1, 44–50 (1987).PubMedGoogle Scholar
  19. 19.
    D. W. Shoemaker, J. T. Gummins, and T. G. Bidder, "Betacarbolines in rat arcuate nucleus," Neuroscience,3, No. 2, 233–239 (1978).PubMedGoogle Scholar
  20. 20.
    P. L. Wood, C. Pilapil, F. La Faille, et al., "3H-tryptamine binding sites in rat brain: distribution and pharmacology," Arch. Int. Pharmacodyn. Thér.,268, No. 2, 194–201 (1984).Google Scholar

Copyright information

© Plenum Publishing Corporation 1990

Authors and Affiliations

  • I. V. Komissarov
  • I. I. Abramets
  • I. M. Samoilovich

There are no affiliations available

Personalised recommendations