ZFIN ID: ZDB-PUB-030211-11
Membrane properties related to the firing behavior of zebrafish motoneurons
Buss, R.R., Bourque, C.W., and Drapeau, P.
Date: 2003
Source: Journal of neurophysiology   89(2): 657-664 (Journal)
Registered Authors: Buss, Robert, Drapeau, Pierre
Keywords: none
MeSH Terms:
  • 4-Aminopyridine/analogs & derivatives*
  • 4-Aminopyridine/pharmacology
  • Action Potentials/drug effects
  • Action Potentials/physiology*
  • Anesthetics, Local/pharmacology
  • Animals
  • Calcium Channels/physiology
  • Cobalt/pharmacology
  • Motor Neurons/physiology*
  • Patch-Clamp Techniques
  • Potassium Channel Blockers/pharmacology
  • Potassium Channels/physiology
  • Sodium Channels/physiology
  • Swimming/physiology
  • Tetraethylammonium/pharmacology
  • Tetrodotoxin/pharmacology
  • Zebrafish
PubMed: 12574443 Full text @ J. Neurophysiol.
The physiological and pharmacological properties of the motoneuron membrane and action potential were investigated in larval zebrafish using whole cell patch current-clamp recording techniques. Action potentials were eliminated in tetrodotoxin, repolarized by tetraethylammonium (TEA) and 3,4-diaminopyridine (3,4-AP)-sensitive potassium conductances, and had a cobalt-sensitive, high-threshold calcium component. Depolarizing current injection evoked a brief (approximately 10-30 ms) burst of action potentials that was terminated by strong, outwardly rectifying voltage-activated potassium and calcium-dependent conductances. In the presence of intracellular cesium ions, a prolonged plateau potential often followed brief depolarizations. During larval development (hatching to free-swimming), the resting membrane conductance increased in a population of motoneurons, which tended to reduce the apparent outward rectification of the membrane. The conductances contributing to action potential burst termination are hypothesized to play a role in patterning the synaptically driven motoneuron output in these rapidly swimming fish.