Summary
-
1.
The effect of veratridine on the electrical properties of giant neurones in the sub-oesophageal ganglion of the snail Helix pomatia has been investigated.
-
2.
Veratridine (10−5 g/ml) caused a depolarization of 14–30 mV. Some of the cells showed slow oscillatory potential changes. The depolarizing effect of veratridine was absent in Na-free saline.
-
3.
Veratridine drastically changed the current-voltage relation: Under voltage clamp conditions the curve was N-shaped, i.e. a branch of negative resistance was obtained. In the current clamp, therefore, a hysteresis curve was observed. The effect depended on the presence of external sodium.
-
4.
Veratridine gave rise to large after-depolarizations of more than 40 sec duration following a short train of spikes. The after-depolarization, but not the spikes, disappeared in Na-free solution.
-
5.
Tetrodotoxin (5×10−6 g/ml) did not influence the veratridine depolarization, the current-voltage curve, the after-depolarization or the spike height.
-
6.
The effects of veratridine are explained by assuming that the alkaloid induces a slow sodium permeability which is voltage dependent and not sensitive to tetrodotoxin.
-
7.
Aconitine (10−4 to 10−3 g/ml) had no effect on the resting potential, the current-voltage relation or the action potential.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Alving, B.: Differences between pacemaker and nonpacemaker neurons of aplysia on voltage clamping. J. gen. Physiol.54, 512–531 (1969).
Benoit, P. H., Coraboeuf, E., Etzensperger, J.: Données microphysiologiques sur la fibre musculaire striée. Microphysiologie comparée des élémentes excitables. C.N.R.S. 1957, p. 29–55.
Frank, G. B.: Effect of veratrine on muscle fibre membrane and on negative afterpotential. J. Neurophysiol.21, 263–278 (1958).
Gerasimov, V. D.: Effect of ion composition of medium on excitation process in giant neurons of snail. Fisiol. Sh. SSSR50, 457–463 (1964).–Fed. Proc.24, T 371–374 (1965).
—: The role of small sodium concentrations in the generation of action potentials in Helix pomatia neurons. Neurofiziol.1, 315–322 (1969) (in Russian).
—, Kostyuk, P. G., Maiskii, V. A.: Influence of divalent cations on electrical characteristics of giant neurone membrane. Biofizika10, 447–453 (1965) (in Russian).
Herzog, W. H., Feibel, R. M., Bryant, S. H.: The effect of aconitine on the giant axon of the squid. J. gen. Physiol.47, 719–733 (1964).
Kerkut, G. A., Thomas, R. C.: An electrogenic sodium pump in snail nerve cells. Comp. Biochem. Physiol.14, 167–183 (1965).
Leicht, R., Meves, H., Wellhöner, H.-H.: Slow changes of membrane permeability in giant neurones of Helix pomatia. Pflügers Arch.323, 63–79 (1971).
Meves, H.: The ionic requirements for the production of action potentials in Helix pomatia neurones. Pflügers Arch.304, 215–241 (1968).
—, Wellhöner, H.: Die Wirkung von Veratridin auf die Riesennervenzellen der Weinbergschnecke. Pflügers Arch.312, R100 (1969).
Parkhomenko, N. T.: On characteristic of the snail giant neurons generating action potentials in sodium free solution. Neurofiziol.2, 100–106 (1970) (in Russian).
Pichon, Y., Boistel, J.: Effects comparés du D. D. T. et de la vératrine sur la perméabilité ionique de la membrane nerveuse d'insecte. J. Physiol. (Paris)61, Suppl. 2, 373–374 (1969).
Redfern, P., Lundh, H., Thesleff, S.: Tetrodotoxin resistant action potentials in denervated rat skeletal muscle. Europ. J. Pharmacol.11, 263–265 (1970).
Straub, R.: Die Wirkung von Veratridin und Ionen auf das Ruhepotential markhaltiger Nervenfasern des Frosches. Helv. physiol. pharmacol. Acta14, 1–28 (1956).
Thomas, R. C.: Membrane current and intracellular sodium changes in a snail neurone during extrusion of injected sodium. J. Physiol. (Lond.)201, 495–514 (1969).
Ulbricht, W.: The effect of veratridine on excitable membranes of nerve and muscle. Ergebn. Physiol.61, 18–71 (1969).
Wellhöner, H.-H.: Effects of aconitine on the slowly adapting stretch receptor neurone of the crayfish. Pflügers Arch.304, 104–117 (1968).
—: The action of veratridine on the membrane potential of the crayfish stretch receptor neurone. Naunyn-Schmiedebergs Arch. Pharmak.267, 185–188 (1970).
—, Conrad, B.: Über die Wirkung von Aconitin auf die Impulstätigkeit in afferenten Fasern aus Lungendehnungsreceptoren. Naunyn-Schmiedebergs Arch. Pharmak. exp. Path.252, 269–285 (1965).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Leicht, R., Meves, H. & Wellhöner, H.H. The effect of veratridine on Helix pomatia neurones. Pflugers Arch. 323, 50–62 (1971). https://doi.org/10.1007/BF00586566
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00586566