Computational model
Stochastic Ih and Na-channels in pyramidal neuron dendrites (Kole et al 2006)
The hyperpolarization-activated cation current (Ih) plays an important role in regulating neuronal excitability, yet its native single-channel properties in the brain are essentially unknown. Here we use variance-mean analysis to study the properties of single Ih channels in the apical dendrites of cortical layer 5 pyramidal neurons in vitro. ... In contrast to the uniformly distributed single-channel conductance, Ih channel number increases exponentially with distance, reaching densities as high as approximately 550 channels/microm2 at distal dendritic sites. These high channel densities generate significant membrane voltage noise. By incorporating a stochastic model of Ih single-channel gating into a morphologically realistic model of a layer 5 neuron, we show that this channel noise is higher in distal dendritic compartments and increased threefold with a 10-fold increased single-channel conductance (6.8 pS) but constant Ih current density. ... These data suggest that, in the face of high current densities, the small single-channel conductance of Ih is critical for maintaining the fidelity of action potential output. See paper for more and details.
  • Neocortex L5/6 pyramidal GLU cell Show Other
  • Neuron or other electrically excitable cell Show Other
  • Kole MH, Hallermann S, Stuart GJ (2006) Show Other
  • Hallermann, Stefan [hallermann at] Show Other
I h
Hallermann, Stefan
Other categories referring to Stochastic Ih and Na-channels in pyramidal neuron dendrites (Kole et al 2006)
Revisions: 20
Last Time: 1/2/2015 10:06:54 PM
Reviewer: Robert A McDougal
Owner: Tom Morse - MoldelDB admin