Summary
Single postganglionic neurones to hairy skin and hairless skin of the hindleg were investigated on spinal cord heating and spinal cord cooling in chloralose anesthetized cats.
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1.
Spontaneously active postganglionic neurones which were classified as vasoconstrictor neurones were depressed by spinal cord heating and excited by spinal cord cooling. The overall response to spinal cord cooling was smaller than that to spinal cord heating.
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2.
Posiganglionic neurones to the hairless skin, which had most likely sudomotor function, responded initially to spinal cord heating with a few impulses or not at all. As judged by the skin potentials recorded from the hairless skin the sweat glands were also only weakly activated at the beginning of the heat stimuli.
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3.
Six silent postganglionic neurones, 3 each to the hairy skin and to the hairless skin, were excited during spinal cord heating. The response of these neurones consisted of a dynamic and a static component and started at the beginning of the heating stimuli with latencies of less than 10 s. The neurones could not be excited by any other stimuli and were classified as cutaneous vasodilator neurones.
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4.
Quantitative analysis of 4 spontaneously active postganglionic (vasoconstrictor) neurones and 3 silent postganglionic (vasodilator) neurones revealed that the threshold of the responses of these neurones to spinal cord heating was 40–42°C (on the dorsal spinal cord) and that the response increase was maximal at the highest temperatures tested (43–44°C).
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References
Beck, L.: Active reflex dilatation in the innervated perfused hindleg of the dog. Amer. J. Physiol.201, 123–128 (1961)
Beck, L.: Histamine as the potential mediator of active reflex dilatation. Fed. Proc.24, 1298–1310 (1965)
Gregor, M., Jänig, W.: Activity in cutaneous and muscle vasoconstrictor neurones during hypoxia, hypercapnia, and asphysia in brain intact and spinobulbar, anaesthetized cats. Pflügers Arch.355, Suppl. R 78 (1975)
Grosse, M., Jänig, W.: Vasoconstrictor and pilomotor fibres in skin nerves to the cat's tail. Pflügers Arch.361, 221–229 (1976)
Hammel, H. T.: Regulation of internal body temperature. Ann. Rev. Physiol.30, 641–710 (1968)
Horeyseck, G., Jänig, W.: Reflexes in postganglionic fibres within skin and muscle nerves following mechanical non-noxious stimulation of skin. Exp. Brain Res.20, 115–123 (1974a)
Horeyseck, G., Jänig, W.: Reflexes in postganglionic fibres within skin and muscle nerves after noxious stimulation of skin. Exp. Brain Res.20, 125–134 (1974b)
Horeyseck, G., Jänig, W., Kirchner, F., Thämer, V.: Activation and inhibition of muscle and cutaneous postganglionic neurones to hindlimb during hypothalamically induced vasoconstriction and atropine-sensitive vasodilation. Pflügers Arch.361, 231–240 (1976)
Iriki, M., Riedel, W., Simon, E.: Regional differentiation of sympathetic activity during hypothalamic heating and cooling in anesthetized rabbits. Pflügers Arch.328, 320–331 (1971)
Jänig, W.: Central organization of somatosympathetic reflexes in vasoconstrictor neurones. Brain Res.87, 305–312 (1975)
Jänig, W., Sato, A., Schmidt, R. F.: Reflexes in postganglionic cutaneous fibres by stimulation of Group I to Group IV somatic afferents. Pflügers Arch.331, 244–256 (1972)
Lisander, B.: Factors influencing the autonomic component of the defence reaction. Acta physiol. scand., Suppl351, 1–42 (1970)
Lloyd, D. P. C.: Evidence of thermal sweating in the foot pad of the cat. Proc. nat. Acad. Sci. (Wash.)49, 492–496 (1963)
Riedel, W., Iriki, M., Simon, E.: Regional differentiation of sympathetic activity during peripheral heating and cooling in anesthetized rabbits. Pflügers Arch.332, 239–247 (1972)
Sato, A., Schmidt, R. F.: Somato-sympathetic reflexes: Afferent fibers, central pathways, discharge characteristics. Physiol. Rev.53, 916–947 (1973)
Schönung, W., Wagner, H., Simon, E.: Neurogenic vasodilatatory component in the thermoregulatory skin blood flow response of the dog. Naunyn-Schmiedeberg's Arch. Pharmacol.273, 230–241 (1972)
Simon, E.: Temperature regulation: The spinal cord as a site of extrahypothalamic thermoregulatory functions. Rev. Physiol. Biochem. Pharmacol.71, 1–76 (1974)
Simon, E., Iriki, M.: Ascending neurons of the spinal cord activated by cold. Experientia (Basel)26, 620–622 (1970)
Simon, E., Iriki, M.: Sensory transmission of spinal heat and cold sensitivity in ascending spinal neurons. Pflügers Arch.328, 103–120 (1971)
Thauer, R.: Thermosensitivity of the spinal cord. In: Physiological and behavioral temperature regulation (J. D. Hardy, A. Ph. Gagge, J. A. J. Stolwijk, eds.), pp. 472–492. Springfield, Ill.: Ch. C. Thomas 1970
Walther, O.-E., Iriki, M., Simon, E.: Antagonistic changes of blood flow and sympathetic activity in different vascular beds following central thermal stimulation. II. Cutaneous and visceral sympathetic activity during spinal cord heating and cooling in anesthetized rabbits and cats. Pflügers Arch.319, 162–184 (1970)
Wang, G. H.: The neural control of sweating, p. 125. Madison: The University of Wisconsin Press 1964
Wünnenberg, W., Brück, K.: Studies on the ascending pathways from the thermosensitive region of the spinal cord. Pflügers Arch.321, 233–241 (1970)
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Gregor, M., Jänig, W. & Riedel, W. Response pattern of cutaneous postganglionic neurones to the hindlimb on spinal cord heating and cooling in the cat. Pflugers Arch. 363, 135–140 (1976). https://doi.org/10.1007/BF01062281
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DOI: https://doi.org/10.1007/BF01062281