Skip Navigation



Chemical Senses Advance Access published online on January 30, 2007
Chemical Senses, doi:10.1093/chemse/bjl059
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
32/4/305    most recent
bjl059v1
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 Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Pézier, A.
Right arrow Articles by Lucas, P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Pézier, A.
Right arrow Articles by Lucas, P.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2007. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oxfordjournals.org

Ca2+ Stabilizes the Membrane Potential of Moth Olfactory Receptor Neurons at Rest and Is Essential for Their Fast Repolarization

Adeline Pézier, Adrien Acquistapace, Michel Renou, Jean-Pierre Rospars and Philippe Lucas

UMR1272 Physiologie de l'Insecte: Signalisation et Communication, INRA, Route de St Cyr, F-78026 Versailles Cedex, France

Correspondence to be sent to: Philippe Lucas, UMR1272 Physiologie de l'Insecte: Signalisation et Communication, INRA, Route de St Cyr, 78026 Versailles Cedex, France. e-mail: plucas{at}versailles.inra.fr


  Abstract

The role of Ca2+ in insect olfactory transduction was studied in the moth Spodoptera littoralis. Single sensillum recordings were made to investigate in vivo the role of sensillar Ca2+ on the electrophysiological properties of sex pheromone responsive olfactory receptor neurons (ORNs). Lowering the sensillar Ca2+ concentration to 2 x 10–8 M increased ORN spontaneous firing activity and induced long bursts of action potentials (APs) superimposed on spontaneous negative deflections of the transepithelial potential. We inferred that Ca2+ stabilizes the membrane potential of ORNs, keeping the spontaneous firing activity at a low and regular level. Neither the amplitude and kinetics of the rising phase of sensillar potentials (SPs) recorded in response to pheromone stimuli nor the AP generation during stimulation depended on the extracellular Ca2+ concentration. Thus, extracellular Ca2+ is not absolutely necessary for ORN response. Partial inhibition of responses with a calmodulin antagonist, W-7, also indicates that intracellular Ca2+ contributes to the ORN response and suggests that Ca2+ release from internal stores is involved. In 2 x 10–8 M Ca2+, the repolarization of the SP was delayed when compared with higher Ca2+ concentrations. Therefore, in contrast to depolarization, ORN repolarization depends on extracellular Ca2+. Ca2+-gated K+ channels identified from cultured ORNs with whole-cell recordings are good candidates to mediate ORN repolarization.

Key words: calcium signaling, depolarization, insect olfactory transduction, patch-clamp, repolarization, single sensillum recording


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Chem SensesHome page
V. Party, C. Hanot, I. Said, D. Rochat, and M. Renou
Plant Terpenes Affect Intensity and Temporal Parameters of Pheromone Detection in a Moth
Chem Senses, November 1, 2009; 34(9): 763 - 774.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.