Die neuronale Grundlage des Zustandes der Narkose: ein vergleichend-physiologischer Ansatz
The sensitivity of flies and locusts to halothane and N2O was investigated. In this paper we report experiments concerning the allover motor activity in the animal as a whole. In order to determine how the size of neurons comes into play under anesthesia we experimented with different but closely related species of flies differing very clearly in size. For the same reason we chose locusts of different developmental states and consequently different size. It came out that the larger insects are more sensitive to anesthetics than the smaller ones.
The results confirm one of Sherrington's (1906) conclusions, which says the axon which conducts spikes cannot be the most sensitive part of the neuron to anesthetic action. He ascribed the highest sensitivity to synapses; this, however, does not match with our results. In agreement with our experimental data is the new hypothesis that long dendrites or axonal endings conducting graded potentials are those parts of the CNS that exhibit the highest sensitivity to anesthetic action. Further confirmation of this hypothesis by more direct approaches has to be provided.
Unable to display preview. Download preview PDF.
- Burrows M (1983) Local interneurones and the control of movement in insects. In: Huber F, Markl H (eds) Neuroethology and behavioral physiology. Springer, Berlin Heidelberg New York, pp 26–41Google Scholar
- Coggshall JC, Boschek CB, Buchner SM (1973) Preliminary investigations on a pair of giant fibers in the central nervous system of dipteran flies. Z Naturforsch 28c:783–784Google Scholar
- Conel (1939–1963) The postnatal development of the human cerebral cortex (7 vols). Harvard University Press, Cambridge, MAGoogle Scholar
- Documenta Geigy. Wissenschaftliche Tabellen. J.R. Geigy A.G. Basel (1955)Google Scholar
- Fischbach KF, heisenberg M (1984) Neurogenetics and behaviour in insects. J Exp Biol 112:65–93Google Scholar
- Halsey MJ (1980) Physicochemical properties of inhalational anaesthetics. In: Gray TC, Utting JE, Nunn JF (eds) General anaesthesia, 4th edn, vol 1. Butterworths, London Boston Sydney Wellington Durban Toronto, pp 45–65Google Scholar
- Hausen K (1984) The lobula-complex of the fly: Structure, function and significance in visual behaviour. In: Ali MA (ed) Photoreception and vision in invertebrates. Series A: Life sciences, vol 74. Nato ASI Series. Plenum Press, New York London, pp 523–559Google Scholar
- Hauser H (1975) Vergleichend quantitative Untersuchungen an den Schganglien der FliegenMusca Domestica undDrosophila melanogaster. Dissertation Universität TübingenGoogle Scholar
- Haydon DA, Hendry BM (1982) Nerve impulse blockage in squid axons byn-alkanes: The effect of axon diameter. J Physiol (London) 333:393–403Google Scholar
- Jack JJB, Noble D, Tsien RW (1975) Electric current flow in excitable cells. Clarendon Press, OxfordGoogle Scholar
- Kandel ER, Siegelbaum S (1985) Principles underlying electrical and chemical synaptic transmission. In: Kandel ER, Schwartz JH (eds) Principles of neural science. Elsevier, New York Amsterdam Oxford, pp 89–107Google Scholar
- Kirschfeld K (1972) The visual system ofMusca: Studies on optics, structure and function. In: Wehner R (ed) Information processing in the visual system of arthropods. Springer, Berlin Heidelberg New York, pp 61–74Google Scholar
- Kirschfeld K, Baier-Rogowski V (1987) The neuronal basis of the anesthetic state: a comparative physiological approach. II The influence of anesthetics on different reactions in flies. Biol Cybern (in preparation)Google Scholar
- Sherrington ChS (1906) The integrative action of the nervous system. Yale University Press, New HavenGoogle Scholar