Skip to main content
NCBI home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1985 May;362:23–38. doi: 10.1113/jphysiol.1985.sp015660

Intracellular pH regulation in the sensory neurone of the stretch receptor of the crayfish (Astacus fluviatilis).

H Moser
PMCID: PMC1192879  PMID: 2410601

Abstract

The ionic mechanisms of intracellular pH (pHi) regulation were studied in the slowly adapting sensory cell of the crayfish stretch receptor by using pH-, Na+- and Cl(-)-sensitive liquid ion exchanger electrodes. Under control conditions a mean pHi of 7.23 +/- 0.12 (S.D.) at a mean membrane potential of 68.3 +/- 4.1 mV S.D. was found in sixteen cells. Thus pHi is about 1 pH unit more alkaline than predicted from passive distribution, implying the presence of an acid extrusion mechanism. In order to acidify the cytoplasm, the cell was either acid-loaded by NH4Cl or exposed to CO2 and CO2/HCO3- solutions. During CO2 exposures pHi was regulated only if calculated amounts of HCO3- were added to keep external pH (pHo) constant. The pHo per se was found to be an important determinant of pHi and its regulation. Substitution of external Na+ by choline inhibited pHi recovery almost completely. As soon as Na+ was readmitted H+ extrusion occurred immediately at a rate similar to that of the control. The internal Na+ activity (aiNa) ranged between 6 and 13 mM with a mean of approximately 9.1 +/- 2.5 mM (S.D.; n = 8). The effects of various solutions on aiNa and the temporal relationship between aiNa and pHi in NH4Cl acid-loaded cells were investigated. The amount of aiNa increased during cell internal acidification and recovered in parallel with pHi recovery in NH4Cl acid-loaded cells. Experiments with 10(-4) M-ouabain and K+-free conditions suggest that neither the Na+-K+ pump nor external K+ are directly involved in pHi regulation. The internal chloride activity (aiCl), which was lower than predicted from a passive distribution, fell during exposure to HCO3-/CO2. Regulation of pHi was inhibited if the cell was completely depleted of Cl- by prolonged exposures to Cl(-)-free solution (isethionate and/or gluconate substituted). The pHi-regulating system of the sensory cell requires Na+ and Cl- which probably operate in a combined mechanism such as Na+ -H+-Cl(-)-HCO3- or an equivalent.

Full text

PDF
23

Selected References

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

  1. Aickin C. C., Deisz R. A., Lux H. D. Ammonium action on post-synaptic inhibition in crayfish neurones: implications for the mechanism of chloride extrusion. J Physiol. 1982 Aug;329:319–339. doi: 10.1113/jphysiol.1982.sp014305. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Aickin C. C., Thomas R. C. An investigation of the ionic mechanism of intracellular pH regulation in mouse soleus muscle fibres. J Physiol. 1977 Dec;273(1):295–316. doi: 10.1113/jphysiol.1977.sp012095. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Aickin C. C., Thomas R. C. Micro-electrode measurement of the internal pH of crab muscle fibres. J Physiol. 1975 Nov;252(3):803–815. doi: 10.1113/jphysiol.1975.sp011171. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Binstock L., Lecar H. Ammonium ion currents in the squid giant axon. J Gen Physiol. 1969 Mar;53(3):342–361. doi: 10.1085/jgp.53.3.342. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Boron W. F., De Weer P. Active proton transport stimulated by CO2/HCO3-, blocked by cyanide. Nature. 1976 Jan 22;259(5540):240–241. doi: 10.1038/259240a0. [DOI] [PubMed] [Google Scholar]
  6. Boron W. F., De Weer P. Intracellular pH transients in squid giant axons caused by CO2, NH3, and metabolic inhibitors. J Gen Physiol. 1976 Jan;67(1):91–112. doi: 10.1085/jgp.67.1.91. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Boron W. F. Intracellular pH transients in giant barnacle muscle fibers. Am J Physiol. 1977 Sep;233(3):C61–C73. doi: 10.1152/ajpcell.1977.233.3.C61. [DOI] [PubMed] [Google Scholar]
  8. Brown H. M., Meech R. W. Intracellular pH and light adaptation in barnacle photoreceptors [proceedings]. J Physiol. 1976 Dec;263(1):218P–218P. [PubMed] [Google Scholar]
  9. Brown H. M., Meech R. W. Light induced changes of internal pH in a barnacle photoreceptor and the effect of internal pH on the receptor potential. J Physiol. 1979 Dec;297(0):73–93. doi: 10.1113/jphysiol.1979.sp013028. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Brown H. M., Ottoson D., Rydqvist B. Crayfish stretch receptor: an investigation with voltage-clamp and ion-sensitive electrodes. J Physiol. 1978 Nov;284:155–179. doi: 10.1113/jphysiol.1978.sp012533. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. CALDWELL P. C. Studies on the internal pH of large muscle and nerve fibres. J Physiol. 1958 Jun 18;142(1):22–62. doi: 10.1113/jphysiol.1958.sp005998. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Deisz R. A., Lux H. D. The role of intracellular chloride in hyperpolarizing post-synaptic inhibition of crayfish stretch receptor neurones. J Physiol. 1982 May;326:123–138. doi: 10.1113/jphysiol.1982.sp014181. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Hino N. Action of ammonium ions on the resting membrane of crayfish stretch receptor neuron. Jpn J Physiol. 1979;29(1):99–102. doi: 10.2170/jjphysiol.29.99. [DOI] [PubMed] [Google Scholar]
  14. Meyer H. The different actions of chloride and potassium on postsynaptic inhibition of an isolated neurone. J Exp Biol. 1976 Apr;64(2):477–487. doi: 10.1242/jeb.64.2.477. [DOI] [PubMed] [Google Scholar]
  15. Moody W. J., Jr The ionic mechanism of intracellular pH regulation in crayfish neurones. J Physiol. 1981 Jul;316:293–308. doi: 10.1113/jphysiol.1981.sp013788. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Moody W., Jr Appearance of calcium action potentials in crayfish slow muscle fibres under conditions of low intracellular pH. J Physiol. 1980 May;302:335–346. doi: 10.1113/jphysiol.1980.sp013246. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Nakajima S., Takahashi K. Post-tetanic hyperpolarization and electrogenic Na pump in stretch receptor neurone of crayfish. J Physiol. 1966 Nov;187(1):105–127. doi: 10.1113/jphysiol.1966.sp008078. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Ozawa S., Tsuda K. Membrane permeability change during inhibitory transmitter action in crayfish stretch receptor cell. J Neurophysiol. 1973 Sep;36(5):805–816. doi: 10.1152/jn.1973.36.5.805. [DOI] [PubMed] [Google Scholar]
  19. Roos A., Boron W. F. Intracellular pH. Physiol Rev. 1981 Apr;61(2):296–434. doi: 10.1152/physrev.1981.61.2.296. [DOI] [PubMed] [Google Scholar]
  20. Russell J. M., Boron W. F., Brodwick M. S. Intracellular pH and Na fluxes in barnacle muscle with evidence for reversal of the ionic mechanism of intracellular pH regulation. J Gen Physiol. 1983 Jul;82(1):47–78. doi: 10.1085/jgp.82.1.47. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Sharp A. P., Thomas R. C. The effects of chloride substitution on intracellular pH in crab muscle. J Physiol. 1981 Mar;312:71–80. doi: 10.1113/jphysiol.1981.sp013616. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Sokolove P. G., Cooke I. M. Inhibition of impulse activity in a sensory neuron by an electrogenic pump. J Gen Physiol. 1971 Feb;57(2):125–163. doi: 10.1085/jgp.57.2.125. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Thomas R. C. Electrogenic sodium pump in nerve and muscle cells. Physiol Rev. 1972 Jul;52(3):563–594. doi: 10.1152/physrev.1972.52.3.563. [DOI] [PubMed] [Google Scholar]
  24. Thomas R. C. The role of bicarbonate, chloride and sodium ions in the regulation of intracellular pH in snail neurones. J Physiol. 1977 Dec;273(1):317–338. doi: 10.1113/jphysiol.1977.sp012096. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Vaughan-Jones R. D., Lederer W. J., Eisner D. A. Ca2+ ions can affect intracellular pH in mammalian cardiac muscle. Nature. 1983 Feb 10;301(5900):522–524. doi: 10.1038/301522a0. [DOI] [PubMed] [Google Scholar]

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

RESOURCES