TABLE 1.
Parameter | Value | Reference | ||
---|---|---|---|---|
Node of Ranvier | ||||
Resistance, Rm | 166.2 kΩ mm2 | Mino et al. 2004 | ||
Capacitance, Cm | 0.5125 nF/mm2 | Mino et al. 2004 | ||
Internode | Tasaki 1955 | |||
Resistance, rm | a | Mino et al. 2004; Cartee 2006 | ||
Capacitance, cm | ||||
Na channel | Matsuoka et al. 2001 | |||
Nernst potential, ENa | 66 mV | |||
Density, ρNa | 80/μm2b | Mino et al. 2004 | ||
Conductance, γNa | 22.65 pS | |||
K channel | ||||
Nernst potential, EK | −88 mV | |||
Density, ρK | 45/μm2b | |||
Conductance, γK | 50.0 pS | |||
Na+ gating kineticsc | A | B | C | Schwarz and Eikhof 1987 |
αm | 1.872 | 25.41 | 6.06 | |
βm | −3.793 | 21.001 | 9.41 | Matsuoka et al. 2001 |
αh | −0.549 | −27.74 | 9.06 | |
βh | 22.57 | 56 | 12.5 | |
K+ gating kineticsc | ||||
αn | 0.129 | 35 | 10 | |
βn | −0.324 | 35 | 10 | |
Axoplasmic resistance, Ra | 6378 Ω mm | Mino et al. 2004 | ||
Resting potential, Erest | −78 mV | Neumcke and Stämpfli 1982 | ||
Extracellular resistivity, ρe | 0.3 kΩ cm | McNeal 1976 |
aε0 is the permittivity of free space (8.854 × 10−12 F/m), εl is the myelin dielectric constant (1.27), lε is the length of compartment one of the nine sub-units of the internode, D is the outer myelinated fiber diameter, d is the unmyelinated (inner) fiber diameter, and ρm is the internodal resistivity (29.26 GΩ mm)
bModified from ρNa = 27/μm2 and ρNa = 10.6/μm2 for producing absolute refractory period = 0.41 ms
c.