Abstract
The brain and spinal cord of the chronic spinal dog contained higher levels of tryptamine than comparable regions of the intact dog. The most significant brain elevations were found in the cerebellum and mesencephalon. Further, tryptamine in the white matter of the spinal cord above the level of transection was higher than below. These findings have been interpreted as indicating that there are tryptaminergic pathways descending in the white matter of the spinal cord from the mesencephalon, cerebellum and rostral spinal cord. The level of tryptamine below the transection was not different from that found in the intact dog, suggesting that there are not only descending but ascending tryptaminergic pathways and that when the axons are transected, tryptamine accumulates proximal to the level of transection.
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Bell, J. A., Martin, W. R.: The effect in the cat of tryptamine (T) and LSD on cutaneous C-fiber (CFR) and polysynaptic (PSR) spinal reflexes. Pharmacologist 15, 161 (1973)
Bell, J. A., Martin, W. R.: The effect of l-tryptophan (TP) on cutaneous C-fiber (CFR) and polysynaptic (PSR) reflexes in acute decerebrate spinal cats and the effect of pretreatment with para-chlorophenylalanine (pCPA) on the action of TP. Fed. Proc. 33, 256 (1974a)
Bell, J. A., Martin, W. R.: Studies of tryptamine and lysergic acid diethylamide (LSD) on cutaneous C-fiber and polysynaptic reflexes in the cat. J. Pharmacol. exp. Ther. 190, 492–500 (1974b)
DiStefano, V., Leary, D. E.: The effect of LSD on inhibitory systems in the spinal cat. Fed. Proc. 17, 364 (1958)
Little, K. D., DiStefano, V., Leary, D. E.: LSD and serotonin effects on spinal reflexes in the cat. J. Pharmacol. exp. Ther. 119, 161 (1957)
Marley, E., Vane, J. R.: Tryptamines and spinal cord reflexes in cats. Brit. J. Pharmacol. 31, 447–465 (1967)
Martin, W. R., Eades, C. G.: A comparison between acute and chronic physical dependence in the chronic spinal dog. J. Pharmacol. exp. Ther. 146, 385–394 (1964)
Martin, W. R., Eades, C. G.: The action of tryptamine on the dog spinal cord and its relationship to the agonistic actions of LSD-like psychotogens. Psychopharmacologia (Berl.) 17, 242–257 (1970)
Martin, W. R., Eades, C. G.: Cross tolerance to tryptamine in the LSD tolerant dog. Psychopharmacologia (Berl.) 27, 93–98 (1972)
Martin, W. R., Eades, C. G.: Effects of phenethylamine (PEA) in the chronic spinal dog. Pharmacologist 16, 205 (1974)
Martin, W. R., Sloan, J. W.: Effects of infused tryptamine in man. Psychopharmacologia (Berl.) 18, 231–237 (1970)
Martin, W. R., Sloan, J. W.: The possible role of tryptamine in brain function and its relationship to the actions of LSD-like hallucinogens. Mt. Sinai J. Med. 41, 276–282 (1974)
Martin, W. R., Sloan, J. W., Buchwald, W. F., Bridges, S. R.: The demonstration of tryptamine in regional perfusates of the dog brain. Psychopharmacologia (Berl.) 37, 189–198 (1974)
Martin, W. R., Sloan, J. W., Christian, S. T., Clements, T. H.: Brain levels of tryptamine. Psychopharmacologia (Berl.) 24, 331–346 (1972)
Philips, S. R., Durden, D. A., Boulten, A. A.: Identification and distribution of tryptamine in the rat. Canad. J. Biochem. 52, 447–451 (1974)
Saavedra, J. M., Axelrod, J.: Effect of drugs on the tryptamine content of rat tissues. J. Pharmacol. exp. Ther. 185, 523–529 (1973)
Sloan, J. W., Martin, W. R., Clements, T. C., Bridges, S. R., Buchwald, W. F.: Brain levels of tryptamine (T) in the cat, dog, guinea pig and rat. Fed. Proc. 33, 468 (1974)
Sloan, J. W., Martin, W. R., Clements, T. H., Buchwald, W. F., Bridges, S. R.: Factors influencing brain and tissue levels of tryptamine: Species, drugs and lesions. J. Neurochem. 24, 523–532 (1975)
Snodgrass, S. R., Horn, A. S.: An assay procedure for tryptamine in brain and spinal cord using its [3H]dansyl derivative. J. Neurochem. 21, 687–696 (1973)
Vaupel, D. B., Martin, W. R.: A comparison of the effects of methoxamine (M), norepinephrine (NE) and tryptamine (T) on segmental reflex activity of the acute spinal cat. Pharmacologist 13, 254 (1971)
Weidmann, H., Cerletti, A.: Die Wirkung von d-Lysergsauere-DiÄthylamid und 5-Hydroxytryptamin (Serotonin) auf spinale Reflexe der Katze. Helv. physiol. pharmacol. Acta 15, 376–383 (1957)
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Martin, W.R., Sloan, J.W., Buchwald, W.F. et al. Neurochemical evidence for tryptaminergic ascending and descending pathways in the spinal cord of the dog. Psychopharmacologia 43, 131–134 (1975). https://doi.org/10.1007/BF00421015
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DOI: https://doi.org/10.1007/BF00421015