Skip to main content
NCBI home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1982 Jan;322:503–528. doi: 10.1113/jphysiol.1982.sp014052

Calcium currents in internally perfused nerve cell bodies of Limnea stagnalis

Lou Byerly 1,2, Susumu Hagiwara 1,2
PMCID: PMC1249685  PMID: 7069629

Abstract

1. When K+ is removed from both sides of the somal membrane of Limnea neurones, time-dependent, voltage-dependent outward currents are observed at positive potentials. These currents can be carried by Tris+ and tetraethylammonium (TEA+), as well as Cs+, but the Cs currents are several times larger. The Cs currents are not affected by external or internal TEA, but are strongly reduced by 4-aminopyridine (4-AP) and all Ca blockers tried.

2. The presence of these non-specific outward currents and their sensitivity to all treatments that eliminate the Ca currents prevent the complete isolation of Ca currents. The non-specific outward currents are most prominent at large positive potentials and as slow tail currents on stepping back to the holding potential.

3. Ca currents are `washed out' in well perfused cells. Typically the Ca current has decayed to less than one tenth of its original size after ½ h of perfusion. This wash-out is specific for the Ca current; Na and K currents persist for several hours.

4. Once the Ca current has completely decayed, it is possible to study one type of non-specific current without overlapping inward currents. This current activates between 0 and +30 mV and appears to reverse near 0 mV.

5. In spite of the probable presence of slowly activating outward currents, the net inward currents measured show little apparent inactivation. In all the cells studied the inward current evoked at +20 mV has never decayed by more than 50% during a 60 ms pulse. So the true inactivation of these Ca currents must be quite slow, with time constants of the order of 100 ms and larger.

6. The activation of the Ca current agrees with m2 kinetics. The rate of activation is the same for Ba currents as for Ca currents.

7. When the membrane potential is stepped back to the holding level (-50 mV), the Ca current turns off quite rapidly with a time constant of about 100 μs (25 °C). The time constant for turning off the Ca current is not related to the time constant for turning on the Ca current at the same voltage as expected for m2 kinetics in the Hodgkin and Huxley model. At -30 mV the τm for turn-on is eight times larger than the τm for turn-off.

Full text

PDF
503

Selected References

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

  1. Adams D. J., Gage P. W. Characteristics of sodium and calcium conductance changes produced by membrane depolarization in an Aplysia neurone. J Physiol. 1979 Apr;289:143–161. doi: 10.1113/jphysiol.1979.sp012729. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Akaike N., Lee K. S., Brown A. M. The calcium current of Helix neuron. J Gen Physiol. 1978 May;71(5):509–531. doi: 10.1085/jgp.71.5.509. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Almers W., Palade P. T. Slow calcium and potassium currents across frog muscle membrane: measurements with a vaseline-gap technique. J Physiol. 1981 Mar;312:159–176. doi: 10.1113/jphysiol.1981.sp013622. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Connor J. A. Time course separation of two inward currents in molluscan neurons. Brain Res. 1977 Jan 7;119(2):487–492. doi: 10.1016/0006-8993(77)90330-4. [DOI] [PubMed] [Google Scholar]
  5. Doroshenko P. A., Kostiuk P. G., Tsyndrenko A. Ia. Issledovanie TEA-ustoichivogo vykhodiashchego toka v somaticheskoi membrane perfuziruemykh nervnykh kletok. Neirofiziologiia. 1979;11(5):460–468. [PubMed] [Google Scholar]
  6. Doroshenko P. A., Kostiuk P. G., Tsyndrenko A. Ia. Issledovanie potentsiala reversii dlia medlennogo komponenta vkhodiashchego toka v membrane neironov molliuskov. Neirofiziologiia. 1978;10(2):206–208. [PubMed] [Google Scholar]
  7. Doroshenko P. A., Kostiuk P. G., Tsyndrenko A. Ia. Razdelenie kalievykh i kal'tsievykh kanalov v membrane somy nervnoi kletki. Neirofiziologiia. 1978;10(6):645–653. [PubMed] [Google Scholar]
  8. Doroshenko P. A., Tsyndrenko A. Ia. Deistvie vnutrikletochnogo kal'tsiia na kal'tsievyi vkhodiashchii tok. Neirofiziologiia. 1978;10(2):203–205. [PubMed] [Google Scholar]
  9. Dunlap K., Fischbach G. D. Neurotransmitters decrease the calcium ocmponent of sensory neurone action potentials. Nature. 1978 Dec 21;276(5690):837–839. doi: 10.1038/276837a0. [DOI] [PubMed] [Google Scholar]
  10. Gorman A. L., Hermann A. Internal effects of divalent cations on potassium permeability in molluscan neurones. J Physiol. 1979 Nov;296:393–410. doi: 10.1113/jphysiol.1979.sp013012. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. 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]
  12. Hagiwara S., Byerly L. Calcium channel. Annu Rev Neurosci. 1981;4:69–125. doi: 10.1146/annurev.ne.04.030181.000441. [DOI] [PubMed] [Google Scholar]
  13. Hagiwara S., Fukuda J., Eaton D. C. Membrane currents carried by Ca, Sr, and Ba in barnacle muscle fiber during voltage clamp. J Gen Physiol. 1974 May;63(5):564–578. doi: 10.1085/jgp.63.5.564. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Hagiwara S., Miyazaki S., Moody W., Patlak J. Blocking effects of barium and hydrogen ions on the potassium current during anomalous rectification in the starfish egg. J Physiol. 1978 Jun;279:167–185. doi: 10.1113/jphysiol.1978.sp012338. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Hagiwara S., Ozawa S., Sand O. Voltage clamp analysis of two inward current mechanisms in the egg cell membrane of a starfish. J Gen Physiol. 1975 May;65(5):617–644. doi: 10.1085/jgp.65.5.617. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Kass R. S., Tsien R. W. Multiple effects of calcium antagonists on plateau currents in cardiac Purkinje fibers. J Gen Physiol. 1975 Aug;66(2):169–192. doi: 10.1085/jgp.66.2.169. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Keynes R. D., Kimura J. E. Activation of the sodium channels in the squid giant axon [proceedings]. J Physiol. 1978 Nov;284:140P–140P. [PubMed] [Google Scholar]
  18. Kostyuk P. G. Calcium ionic channels in electrically excitable membrane. Neuroscience. 1980;5(6):945–959. doi: 10.1016/0306-4522(80)90178-5. [DOI] [PubMed] [Google Scholar]
  19. Kostyuk P. G., Krishtal O. A. Effects of calcium and calcium-chelating agents on the inward and outward current in the membrane of mollusc neurones. J Physiol. 1977 Sep;270(3):569–580. doi: 10.1113/jphysiol.1977.sp011969. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Kostyuk P. G., Krishtal O. A., Pidoplichko V. I. Asymmetrical displacement currents in nerve cell membrane and effect of internal fluoride. Nature. 1977 May 5;267(5606):70–72. doi: 10.1038/267070a0. [DOI] [PubMed] [Google Scholar]
  21. Kostyuk P. G., Krishtal O. A., Pidoplichko V. I. Calcium inward current and related charge movements in the membrane of snail neurones. J Physiol. 1981 Jan;310:403–421. doi: 10.1113/jphysiol.1981.sp013557. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Kostyuk P. G., Krishtal O. A., Pidoplichko V. I. Effect of internal fluoride and phosphate on membrane currents during intracellular dialysis of nerve cells. Nature. 1975 Oct 23;257(5528):691–693. doi: 10.1038/257691a0. [DOI] [PubMed] [Google Scholar]
  23. Kostyuk P. G., Krishtal O. A., Shakhovalov Y. A. Separation of sodium and calcium currents in the somatic membrane of mollusc neurones. J Physiol. 1977 Sep;270(3):545–568. doi: 10.1113/jphysiol.1977.sp011968. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Kryshtal' O. A., Pidoplichko V. I. Vnutrikletochnaia perfuziia gigantskikh neironov ulitki. Neirofiziologiia. 1975;7(3):327–329. [PubMed] [Google Scholar]
  25. Lee K. S., Akaike N., Brown A. M. Properties of internally perfused, voltage-clamped, isolated nerve cell bodies. J Gen Physiol. 1978 May;71(5):489–507. doi: 10.1085/jgp.71.5.489. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Lee K. S., Akaike N., Brown A. M. Trypsin inhibits the action of tetrodotoxin on neurones. Nature. 1977 Feb 24;265(5596):751–753. doi: 10.1038/265751a0. [DOI] [PubMed] [Google Scholar]
  27. 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]
  28. Reuter H. Localization of beta adrenergic receptors, and effects of noradrenaline and cyclic nucleotides on action potentials, ionic currents and tension in mammalian cardiac muscle. J Physiol. 1974 Oct;242(2):429–451. doi: 10.1113/jphysiol.1974.sp010716. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Reuter H., Scholz H. The regulation of the calcium conductance of cardiac muscle by adrenaline. J Physiol. 1977 Jan;264(1):49–62. doi: 10.1113/jphysiol.1977.sp011657. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Tsien R. W. Adrenaline-like effects of intracellular iontophoresis of cyclic AMP in cardiac Purkinje fibres. Nat New Biol. 1973 Sep 26;245(143):120–122. doi: 10.1038/newbio245120a0. [DOI] [PubMed] [Google Scholar]

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

RESOURCES