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. 1971 Jul 1;58(1):36–53. doi: 10.1085/jgp.58.1.36

Two Fast Transient Current Components during Voltage Clamp on Snail Neurons

Erwin Neher 1
PMCID: PMC2226007  PMID: 5564761

Abstract

Voltage clamp currents from medium sized ganglion cells of Helix pomatia have a fast transient outward current component in addition to the usually observed inward and outward currents. This component is inactivated at normal resting potential. The current, which is carried by K+ ions, may surpass leakage currents by a factor of 100 after inactivation has been removed by hyperpolarizing conditioning pulses. Its kinetics are similar to those of the inward current, except that it has a longer time constant of inactivation. It has a threshold close to resting potential. This additional component is also present in giant cells, where however, it is less prominent. Pacemaker activity is controlled by this current. It was found that inward currents have a slow inactivating process in addition to a fast, Hodgkin-Huxley type inactivation. The time constants of the slow process are similar to those of slow outward current inactivation.

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Selected References

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

  1. ARAKI T., TERZUOLO C. A. Membrane currents in spinal motoneurons associated with the action potential and synaptic activity. J Neurophysiol. 1962 Nov;25:772–789. doi: 10.1152/jn.1962.25.6.772. [DOI] [PubMed] [Google Scholar]
  2. Adelman W. J., Jr, Palti Y. The effects of external potassium and long duration voltage conditioning on the amplitude of sodium currents in the giant axon of the squid, Loligo pealei. J Gen Physiol. 1969 Nov;54(5):589–606. doi: 10.1085/jgp.54.5.589. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Alving B. O. Differences between pacemaker and nonpacemaker neurons of Aplysia on voltage clamping. J Gen Physiol. 1969 Oct;54(4):512–531. doi: 10.1085/jgp.54.4.512. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Binstock L., Goldman L. Current- and voltage-clamped studies on Myxicola giant axons. Effect of tetrodotoxin. J Gen Physiol. 1969 Dec;54(6):730–740. doi: 10.1085/jgp.54.6.730. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Chandler W. K., Meves H. Slow changes in membrane permeability and long-lasting action potentials in axons perfused with fluoride solutions. J Physiol. 1970 Dec;211(3):707–728. doi: 10.1113/jphysiol.1970.sp009300. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. FRANKENHAEUSER B., HUXLEY A. F. THE ACTION POTENTIAL IN THE MYELINATED NERVE FIBER OF XENOPUS LAEVIS AS COMPUTED ON THE BASIS OF VOLTAGE CLAMP DATA. J Physiol. 1964 Jun;171:302–315. doi: 10.1113/jphysiol.1964.sp007378. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Geduldig D., Gruener R. Voltage clamp of the Aplysia giant neurone: early sodium and calcium currents. J Physiol. 1970 Nov;211(1):217–244. doi: 10.1113/jphysiol.1970.sp009276. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Guttman R., Barnhill R. Oscillation and repetitive firing in squid axons. Comparison of experiments with computations. J Gen Physiol. 1970 Jan;55(1):104–118. doi: 10.1085/jgp.55.1.104. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. HAGIWARA S., SAITO N. Voltage-current relations in nerve cell membrane of Onchidium verruculatum. J Physiol. 1959 Oct;148:161–179. doi: 10.1113/jphysiol.1959.sp006279. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. HODGKIN A. L., HUXLEY A. F. A quantitative description of membrane current and its application to conduction and excitation in nerve. J Physiol. 1952 Aug;117(4):500–544. doi: 10.1113/jphysiol.1952.sp004764. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. JULIAN F. J., MOORE J. W., GOLDMAN D. E. Current-voltage relations in the lobster giant axon membrane under voltage clamp conditions. J Gen Physiol. 1962 Jul;45:1217–1238. doi: 10.1085/jgp.45.6.1217. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Neher E., Lux H. D. Properties of somatic membrane patches of snail neurons under voltage clamp. Pflugers Arch. 1971;322(1):35–38. doi: 10.1007/BF00586662. [DOI] [PubMed] [Google Scholar]
  13. Neher E., Lux H. D. Voltage clamp on Helix pomatia neuronal membrane; current measurement over a limited area of the soma surface. Pflugers Arch. 1969;311(3):272–277. doi: 10.1007/BF00590532. [DOI] [PubMed] [Google Scholar]

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