Nav1p6_MA2020_GoC#
- class braincell.channel.Nav1p6_MA2020_GoC(size, temp=Quantity(295.15, 'K'), g_max=Quantity(16., 'mS / cm^2'), name=None, solver=None, substeps=None)#
Resurgent Nav1.6 sodium current, Golgi-cell parameterisation.
The 13-state Raman & Bean [1] / Khaliq et al. [2] resurgent sodium Markov scheme, as implemented by Akemann & Knopfel (2006) [3] and parameterised for the Golgi cell model of (Masoli et al., 2020) [4]. Five closed states
C1-C5form an activation ladder that opens intoO;Ocan additionally transition into a blocked stateB(the resurgent-current mechanism) or into a deep-inactivated stateI6; each closed stateCnhas a matching inactivated stateIn(n = 1..5), themselves connected in the same ladder topology as the closed states and converging onI6fromI5.I6is eliminated algebraically (dependent_state).\[\begin{split}\begin{aligned} f_{0,n} &= (5-n)\,\alpha \exp(V'/x_1)\,\phi, &\quad b_{0,n} &= n\,\beta \exp((V' + v_a)/(x_2 + v_k))\,\phi \\ f_{0O} &= \gamma \exp(V'/x_3)\,\phi, &\quad b_{0O} &= \delta \exp(V'/x_4)\,\phi \\ f_{ip} &= \epsilon \exp(V'/x_5)\,\phi, &\quad b_{ip} &= \zeta \exp(V'/x_6)\,\phi \\ f_{1,n} &= (5-n)\,\alpha\,a \exp((V' + v_i)/x_1)\,\phi, &\quad b_{1,n} &= n\,\beta\,b \exp((V' + v_i)/x_2)\,\phi \\ f_{1n} &= \gamma \exp(V'/x_3)\,\phi, &\quad b_{1n} &= \delta \exp(V'/x_4)\,\phi \\ f_{i,n} &= C_{on}\,a^{\,n-1}\,\phi, &\quad b_{i,n} &= C_{off}\,b^{\,n-1}\,\phi \\ f_{in} &= O_{on}\,\phi, &\quad b_{in} &= O_{off}\,\phi \end{aligned}\end{split}\]for \(n = 1..4\) (\(f_{0,n}\)/\(b_{0,n}\), \(f_{1,n}\)/\(b_{1,n}\)) and \(n = 1..5\) (\(f_{i,n}\)/\(b_{i,n}\)), where \(V' = V/\mathrm{mV}\), \(a\) =
alfac\(= (O_{on}/C_{on})^{1/4}\), \(b\) =btfac\(= (O_{off}/C_{off})^{1/4}\), and \(\phi = 3^{(T - 22)/10}\) with \(T\) in degrees Celsius. The current is \(g_{max} \cdot O \cdot (E_{Na} - V)\), taken directly from the open-state occupancy rather than apower-weighted gate product.- Parameters:
size (
int|Sequence[int] |integer|Sequence[integer]) – Channel state shape.temp (
Array|ndarray|bool|number|bool|int|float|complex|Quantity) – Absolute temperature driving the \(\phi\) factor, default 22 degrees Celsius (the reference temperature itself, so \(\phi = 1\)).g_max (
Array|ndarray|bool|number|bool|int|float|complex|Quantity|Callable) – Maximal conductance density, default16.0 mS/cm2.solver (
str|None) – Override forMarkov’s default ODE solver.substeps (
int|None) – Override forMarkov’s default substep count.
See also
Nav1p6_MA2024_PCSame scheme and constants, Purkinje-cell model citation.
Nav1p6_MA2025_BCSame scheme and constants, basket-cell model citation.
Nav1p6_RI2021_SCSame scheme and constants, stellate-cell model citation.
Nav1p1_MA2025_BCSame 13-state topology with an independently overridden constant set for the non-resurgent Nav1.1 variant.
Notes
Ported from
Nav1p6_MA20_GoC.mod. All ofCon,Coff,Oon,Ooff,alpha,beta,gamma,delta,epsilon,zeta,x1-x6,vshifta,vshifti,vshiftk,alfacandbtfacare fixed internal constants set in__init__and are not exposed as__init__parameters.No import deviation (
TABLEremoval,derivimplicit->cnexpsubstitution, rate-refresh relocation, or NMODL default-precision rewrite) is recorded for this mechanism in the bibliography’sMA2020import-deviations tables.References
- current(V, Na)[source]#
Calculate the current for this ion channel.
This method should be implemented by subclasses to compute the current based on the channel’s specific properties and state.
- Parameters:
*args – Variable length argument list.
**kwargs – Arbitrary keyword arguments.
- Raises:
NotImplementedError – This method must be implemented by subclasses.