English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Initiation and propagation of calcium−dependent action potentials in a coupled network of olfactory interneurons

MPS-Authors
/persons/resource/persons128986

Denk,  Winfried
Department of Biomedical Optics, Max Planck Institute for Medical Research, Max Planck Society;

External Resource
No external resources are shared
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available
Citation

Wang, J. W., Denk, W., Flores, J., & Gelperin, A. (2001). Initiation and propagation of calcium−dependent action potentials in a coupled network of olfactory interneurons. Journal of Neurophysiology, 85(2), 977-985. Retrieved from http://jn.physiology.org/cgi/content/abstract/85/2/977.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0019-A0D9-A
Abstract
Coherent oscillatory electrical activity and apical−basal wave propagation have been described previously in the procerebral (PC) lobe, an olfactory center of the terrestrial slug Limax maximus. In this study, we investigate the physiological basis of oscillatory activity and wave propagation in the PC lobe. Calcium green dextran was locally deposited in the PC lobe; this led to cellular uptake and transport of dye by bursting and nonbursting neurons of the PC lobe. The change of intracellular calcium concentration was measured at several different positions in neurites of individual bursting neurons in the PC lobe with a two−photon laser−scanning microscope. Fluorescence measurements were also made from neurons intracellularly injected with calcium green−1. Two different morphological classes of bursting neurons were found, varicose (VB) and smooth (SB). Our results from concurrent optical and intracellular recordings suggest that Ca2+ is the major carrier for the inward current during action potentials of bursting neurons. Intracellular recordings from bursting neurons with nystatin perforated−patch electrodes made while simultaneously recording the local field potential (LFP) with extracellular electrodes indicate that the burster spikes are precisely phase−locked to the periodic LFP events. By referencing successive calcium measurements to the common LFP signal, we could therefore accurately determine the relative timing of calcium transients at different points along a neurite. Measuring the relation of temporal to spatial differences allowed us to estimate the velocity of action potential propagation, which was 4.3 ? 0.2 (SE) mm/s in VBs, and 1.3 ? 0.2 mm/s in SB