Am J Physiol Cell Physiol Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Cell Physiol 271: C1817-C1827, 1996;
0363-6143/96 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Sugasawa, M.
Right arrow Articles by Dulon, D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sugasawa, M.
Right arrow Articles by Dulon, D.

AJP - Cell Physiology, Vol 271, Issue 6 C1817-C1827, Copyright © 1996 by American Physiological Society

ARTICLES

ATP activates a cation conductance and Ca(2+)-dependent Cl- conductance in Hensen cells of guinea pig cochlea

M. Sugasawa, C. Erostegui, C. Blanchet and D. Dulon
Laboratoire d'Audiologie Experimentale, Institut National de la Sante et de la Recherche Medicale, Hopital Pellegrin, Bordeaux, France.

Simultaneous whole cell patch-clamp and indo 1 fluorescence measurements were used to characterize ATP-evoked membrane currents and intracellular Ca2+ concentration ([Ca2+]i) changes in isolated Hensen cells of the guinea pig organ of Corti. At negative holding potential, ATP activated a biphasic inward current and a concomitant increase in [Ca2+]i. The initial current activated within < 50 ms, showed a reversal potential near 0 mV and was reversibly inhibited by 30 microM suramin, suggesting this conductance was mediated by ATP-gated nonselective cation channels. The delayed ATP-activated current was mainly carried by Cl- as indicated by its shift in reversal potential when intracellular Cl- was replaced by gluconate. This Cl- conductance appeared to be Ca(2+)-activated secondarily to Ca2+ influx, since it required the presence of extracellular Ca2+ and was suppressed when an intracellular solution containing 10 mM 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid was used. In the absence of extracellular Ca2+, ATP still increased [Ca2+]i concomitant with a monophasic inward cation current, indicating Ca2+ release from intracellular stores. We conclude that Hensen cells have ionotropic and metabotropic P2 purinoceptors. They also have Ca(2+)-activated Cl- channels that can be activated by extracellular ATP, suggesting that purinoceptors in Hensen cells could play a regulatory role in ion and water balance of cochlear fluids.


This article has been cited by other articles:


Home page
 J. Neurophysiol.Home page
C. Chen, M. S. Parker, A. P. Barnes, P. Deininger, and R. P. Bobbin
Functional Expression of Three P2X2 Receptor Splice Variants From Guinea Pig Cochlea
J Neurophysiol, March 1, 2000; 83(3): 1502 - 1509.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurosci.Home page
G. D. Housley, R. Kanjhan, N. P. Raybould, D. Greenwood, S. G. Salih, L. Jarlebark, L. D. Burton, V. C. M. Setz, M. B. Cannell, C. Soeller, et al.
Expression of the P2X2 Receptor Subunit of the ATP-Gated Ion Channel in the Cochlea: Implications for Sound Transduction and Auditory Neurotransmission
J. Neurosci., October 1, 1999; 19(19): 8377 - 8388.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Cell Physiol.Home page
D. B. Light, T. L. Capes, R. T. Gronau, and M. R. Adler
Extracellular ATP stimulates volume decrease in Necturus red blood cells
Am J Physiol Cell Physiol, September 1, 1999; 277(3): C480 - C491.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online