Skip to main content
NCBI home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1980 Jan;298:145–157. doi: 10.1113/jphysiol.1980.sp013072

Voltage, temperature and ionic dependence of the slow outward current in Aplysia burst-firing neurones.

D Johnston
PMCID: PMC1279107  PMID: 7359382

Abstract

1. The slow outward current in Aplysia burst-firing neurones was studied under voltage-clamp conditions. This current, designated Iso, was measured as the incremental outward tail current following small depolarizing commands. 2. Iso was shown to be a pure K+ current, probably activated by the influx of Ca2+ during the depolarizing command (Johnston, 1976). For small depolarizations, the peak conductance was about 10(-7) mhos. 3. The rate of decay of Iso could be fit by a single exponential and was voltage-dependent, increasing with depolarization. 4. The decay rate of Iso was also temperature-dependent, with a Q10 of about 3. The peak conductance, however, was much less temperature-sensitive, with a Q10 of about 1.5. 5. The voltage dependence of decay rate suggested either the presence of a voltage-dependent Ca2+ pump or that the change in intracellular calcium concentration was not the rate-limiting step in the decay of Iso.

Full text

PDF
145

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. ARVANITAKI-CHALAZONITIS A., CHALAZONITIS N. Les potentiels bioélectriques endocytaires du neurone géant d'Aplysia en activité autorythmique. C R Hebd Seances Acad Sci. 1955 Jan 17;240(3):349–351. [PubMed] [Google Scholar]
  2. ARVANITAKI A., CHALAZONITIS N. Configurations modales de l'activité, propres à différents neurones d'un mëme centre. J Physiol (Paris) 1958 Mar;50(2):122–125. [PubMed] [Google Scholar]
  3. Anderson C. R., Stevens C. F. Voltage clamp analysis of acetylcholine produced end-plate current fluctuations at frog neuromuscular junction. J Physiol. 1973 Dec;235(3):655–691. doi: 10.1113/jphysiol.1973.sp010410. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Blaustein M. P. The interrelationship between sodium and calcium fluxes across cell membranes. Rev Physiol Biochem Pharmacol. 1974;70:33–82. doi: 10.1007/BFb0034293. [DOI] [PubMed] [Google Scholar]
  5. Brehm P., Eckert R. Calcium entry leads to inactivation of calcium channel in Paramecium. Science. 1978 Dec 15;202(4373):1203–1206. doi: 10.1126/science.103199. [DOI] [PubMed] [Google Scholar]
  6. Brodwick M. S., Junge D. Post-stimulus hyperpolarization and slow potassium conductance increase in Aplysia giant neurone. J Physiol. 1972 Jun;223(2):549–570. doi: 10.1113/jphysiol.1972.sp009862. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Brown A. M., Brodwick M. S., Eaton D. C. Intracellular calcium and extra-retinal photoreception of Aplysia Giant neurons. J Neurobiol. 1977 Jan;8(1):1–18. doi: 10.1002/neu.480080102. [DOI] [PubMed] [Google Scholar]
  8. Charlton R. R., Wenner C. E. Calcium-ion transport by intact Ehrlich ascites-tumour cells. Role of respiratory substrates, Pi and temperature. Biochem J. 1978 Mar 15;170(3):537–544. doi: 10.1042/bj1700537. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Eaton D. C. Potassium ion accumulation near a pace-making cell of Aplysia. J Physiol. 1972 Jul;224(2):421–440. doi: 10.1113/jphysiol.1972.sp009903. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Eckert R., Lux H. D. A voltage-sensitive persistent calcium conductance in neuronal somata of Helix. J Physiol. 1976 Jan;254(1):129–151. doi: 10.1113/jphysiol.1976.sp011225. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. FRANKENHAEUSER B., MOORE L. E. THE EFFECT OF TEMPERATURE ON THE SODIUM AND POTASSIUM PERMEABILITY CHANGES IN MYELINATED NERVE FIBRES OF XENOPUS LAEVIS. J Physiol. 1963 Nov;169:431–437. doi: 10.1113/jphysiol.1963.sp007269. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Gorman A. L., Thomas M. V. Changes in the intracellular concentration of free calcium ions in a pace-maker neurone, measured with the metallochromic indicator dye arsenazo III. J Physiol. 1978 Feb;275:357–376. doi: 10.1113/jphysiol.1978.sp012194. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. HODGKIN A. L., HUXLEY A. F. Currents carried by sodium and potassium ions through the membrane of the giant axon of Loligo. J Physiol. 1952 Apr;116(4):449–472. doi: 10.1113/jphysiol.1952.sp004717. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. HODGKIN A. L., HUXLEY A. F., KATZ B. Measurement of current-voltage relations in the membrane of the giant axon of Loligo. J Physiol. 1952 Apr;116(4):424–448. doi: 10.1113/jphysiol.1952.sp004716. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Johnston D. Voltage clamp reveals basis for calcium regulation of bursting pacemaker potentials in Aplysia neurons. Brain Res. 1976 May 7;107(2):418–423. doi: 10.1016/0006-8993(76)90239-0. [DOI] [PubMed] [Google Scholar]
  16. Junge D., Stephens C. L. Cyclic variation of potassium conductance in a burst-generating neurone in Aplysia. J Physiol. 1973 Nov;235(1):155–181. doi: 10.1113/jphysiol.1973.sp010382. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Kandel E. R., Tauc L. Anomalous rectification in the metacerebral giant cells and its consequences for synaptic transmission. J Physiol. 1966 Mar;183(2):287–304. doi: 10.1113/jphysiol.1966.sp007867. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Lee K. S., Shin B. C. Studies on the active transport of calcium in human red cells. J Gen Physiol. 1969 Dec;54(6):713–729. doi: 10.1085/jgp.54.6.713. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Magleby K. L., Stevens C. F. The effect of voltage on the time course of end-plate currents. J Physiol. 1972 May;223(1):151–171. doi: 10.1113/jphysiol.1972.sp009839. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Marmor M. F. The effects of temperature and ions on the current-voltage relation and electrical characteristics of a molluscan neurone. J Physiol. 1971 Nov;218(3):573–598. doi: 10.1113/jphysiol.1971.sp009634. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Meech R. W. Intracellular calcium injection causes increased potassium conductance in Aplysia nerve cells. Comp Biochem Physiol A Comp Physiol. 1972 Jun 1;42(2):493–499. doi: 10.1016/0300-9629(72)90128-4. [DOI] [PubMed] [Google Scholar]
  22. Meech R. W. The sensitivity of Helix aspersa neurones to injected calcium ions. J Physiol. 1974 Mar;237(2):259–277. doi: 10.1113/jphysiol.1974.sp010481. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Partridge L. D., Stevens C. F. A mechanism for spike frequency adaptation. J Physiol. 1976 Apr;256(2):315–332. doi: 10.1113/jphysiol.1976.sp011327. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Russell J. M., Brown A. M. Active transport of potassium by the giant neuron of the aplysia abdominal ganglion. J Gen Physiol. 1972 Nov;60(5):519–533. doi: 10.1085/jgp.60.5.519. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Smith T. G., Jr, Barker J. L., Gainer H. Requirements for bursting pacemaker potential activity in molluscan neurones. Nature. 1975 Feb 6;253(5491):450–452. doi: 10.1038/253450a0. [DOI] [PubMed] [Google Scholar]
  26. Thompson S. H. Three pharmacologically distinct potassium channels in molluscan neurones. J Physiol. 1977 Feb;265(2):465–488. doi: 10.1113/jphysiol.1977.sp011725. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Whisler J. W., Johnston D. Epileptogenesis: a model for the involvement of slow membrane events and extracellular potassium. J Theor Biol. 1978 Dec 7;75(3):271–278. doi: 10.1016/0022-5193(78)90334-x. [DOI] [PubMed] [Google Scholar]
  28. Wilson W. A., Wachtel H. Negative resistance characteristic essential for the maintenance of slow oscillations in bursting neurons. Science. 1974 Dec 6;186(4167):932–934. doi: 10.1126/science.186.4167.932. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Physiology are provided here courtesy of The Physiological Society

RESOURCES