Skip to main content
PMC home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1979 Aug;293:329–345. doi: 10.1113/jphysiol.1979.sp012892

The nature of the negative endocochlear potentials produced by anoxia and ethacrynic acid in the rat and guinea-pig.

S K Bosher
PMCID: PMC1280716  PMID: 41092

Abstract

1. The alterations in the Na+ and K+ concentrations of the cochlear endolymph and in the endocochlear potential were followed simultaneously by means of ion-sensitive and conventional micro-electrodes during simple anoxia, during anoxia after i.v. ethacrynic acid and after i.v. ethacrynic acid alone. The endolymphatic pH changes were measured separately and the effect of perilymphatic ethacrynic acid upon the endocochlear potential was investigated. 2. The over-all Na+:K+ permeability ratio for the endolymph system was determined in individual animals for the first time using an indirect method. The normal mean values of 0.27 (rat) and 0.38 (guinea-pig) were increased after ethacrynic acid. Permeability changes occurred during anoxia but were delayed in onset. 3. The negative endocochlear potentials in each situation behaved quantitatively like modified K+ diffusion potentials largely dependent upon the K+ and Na+ gradients between endolymph and perilymph.

Full text

PDF
330

Selected References

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

  1. Bosher S. K., Smith C., Warren R. L. The effects of ethacrynic acid upon the cochlear endolymph and stria vascularis. A preliminary report. Acta Otolaryngol. 1973 Feb-Mar;75(2):184–191. doi: 10.3109/00016487309139694. [DOI] [PubMed] [Google Scholar]
  2. Bosher S. K., Warren R. L. A study of the electrochemistry and osmotic relationships of the cochlear fluids in the neonatal rat at the time of the development of the endocochlear potential. J Physiol. 1971 Feb;212(3):739–761. doi: 10.1113/jphysiol.1971.sp009354. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bosher S. K., Warren R. L. Observations on the electrochemistry of the cochlear endolymph of the rat: a quantitative study of its electrical potential and ionic composition as determined by means of flame spectrophotometry. Proc R Soc Lond B Biol Sci. 1968 Nov 5;171(1023):227–247. doi: 10.1098/rspb.1968.0066. [DOI] [PubMed] [Google Scholar]
  4. Bosher S. K., Warren R. L. Very low calcium content of cochlear endolymph, an extracellular fluid. Nature. 1978 Jun 1;273(5661):377–378. doi: 10.1038/273377a0. [DOI] [PubMed] [Google Scholar]
  5. Burg M., Green N. Effect of ethacrynic acid on the thick ascending limb of Henle's loop. Kidney Int. 1973 Nov;4(5):301–308. doi: 10.1038/ki.1973.121. [DOI] [PubMed] [Google Scholar]
  6. HODGKIN A. L., KATZ B. The effect of sodium ions on the electrical activity of giant axon of the squid. J Physiol. 1949 Mar 1;108(1):37–77. doi: 10.1113/jphysiol.1949.sp004310. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. HONRUBIA V., JOHNSTONE B. M., BUTLER R. A. MAINTENANCE OF COCHLEAR POTENTIALS DURING ASPHYXIA. Acta Otolaryngol. 1965 Jul-Aug;60:105–112. doi: 10.3109/00016486509126993. [DOI] [PubMed] [Google Scholar]
  8. Honrubia V., Strelioff D., Sitko S. T. Physiological basis of cochlear transduction and sensitivity. Ann Otol Rhinol Laryngol. 1976 Nov-Dec;85(6 Pt 1):697–710. doi: 10.1177/000348947608500601. [DOI] [PubMed] [Google Scholar]
  9. JOHNSTONE B. M. THE RELATION BETWEEN ENDOLYMPH AND THE ENDOCOCHLEAR POTENTIAL DURING ANOXIA. Acta Otolaryngol. 1965 Jul-Aug;60:113–120. doi: 10.3109/00016486509126994. [DOI] [PubMed] [Google Scholar]
  10. Konishi T., Kelsey E. Effect of potassium deficiency on cochlear potentials and cation contents of the endolymph. Acta Otolaryngol. 1973 Dec;76(6):410–418. doi: 10.3109/00016487309121529. [DOI] [PubMed] [Google Scholar]
  11. Kuijpers W., Bonting S. L. The cochlear potentials. II. The nature of the cochlear endolymphatic resting potential. Pflugers Arch. 1970;320(4):359–372. doi: 10.1007/BF00588214. [DOI] [PubMed] [Google Scholar]
  12. Kusakari J., Ise I., Comegys T. H., Thalmann I., Thalmann R. Effect of ethacrynic acid, furosemide, and ouabain upon the endolymphatic potential and upon high energy phosphates of the stria vascularis. Laryngoscope. 1978 Jan;88(1 Pt 1):12–37. doi: 10.1002/lary.1978.88.1.12. [DOI] [PubMed] [Google Scholar]
  13. Kusakari J., Thalmann R. Effects of anoxia and ethacrynic acid upon ampullar endolymphatic potential and upon high energy phosphates in ampullar wall. Laryngoscope. 1976 Jan;86(1):132–147. doi: 10.1288/00005537-197601000-00025. [DOI] [PubMed] [Google Scholar]
  14. MISRAHY G. A., HILDRETH K. M., CLARK L. C., SHINABARGER E. W. Measurement of the pH of the endolymph in the cochlea of guinea pigs. Am J Physiol. 1958 Aug;194(2):393–395. doi: 10.1152/ajplegacy.1958.194.2.393. [DOI] [PubMed] [Google Scholar]
  15. Melichar I., Syka J. The effects of ethacrynic acid upon the potassium concentration in guinea pig cochlear fluids. Hear Res. 1978 Oct;1(1):35–41. doi: 10.1016/0378-5955(78)90007-2. [DOI] [PubMed] [Google Scholar]
  16. Melichar I., Syka J. Time course of anoxia-induced K+ concentration changes in the cochlea measured with K+ specific microelectrodes. Pflugers Arch. 1977;372(3):207–213. doi: 10.1007/BF01063854. [DOI] [PubMed] [Google Scholar]
  17. Prazma J. Passive ion transport through the Reissner membrane. Acta Otolaryngol. 1969 Jul-Aug;68(1):53–61. doi: 10.3109/00016486909121542. [DOI] [PubMed] [Google Scholar]
  18. Sellick P. M., Bock G. R. Evidence for an electrogenic potassium pump as the origin of the positive component of the endocochlear potential. Pflugers Arch. 1974;352(4):351–361. doi: 10.1007/BF00585687. [DOI] [PubMed] [Google Scholar]
  19. Sellick P. M., Johnstone B. M. Changes in cochlear endolymph Na + concentration measured with Na + specific microelectrodes. Pflugers Arch. 1972;336(1):11–20. doi: 10.1007/BF00589137. [DOI] [PubMed] [Google Scholar]
  20. Sellick P. M., Johnstone B. M. Differential effects of ouabain and ethacrynic acid on the labyrinthine potentials. Pflugers Arch. 1974;352(4):339–350. doi: 10.1007/BF00585686. [DOI] [PubMed] [Google Scholar]
  21. Sellick P. M., Johnstone B. M. Production and role of inner ear fluid. Prog Neurobiol. 1975;5(4):337–362. doi: 10.1016/0301-0082(75)90015-5. [DOI] [PubMed] [Google Scholar]
  22. Thalmann R., Kusakari J., Miyoshi T. Dysfunctions of energy releasing and consuming processes of the cochlea. Laryngoscope. 1973 Oct;83(10):1690–1712. doi: 10.1288/00005537-197310000-00010. [DOI] [PubMed] [Google Scholar]
  23. Thalmann R., Miyoshi T., Thalmann I. The influence of ischemia upon the energy reserves of inner ear tissues. Laryngoscope. 1972 Dec;82(12):2249–2272. doi: 10.1288/00005537-197212000-00013. [DOI] [PubMed] [Google Scholar]

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

RESOURCES