def create_cell():
"""
"""
mycell = Neuron(Passive, ApicalBasalActive)
# homogeneous distribution of passive properties
mycell.passive(Cm = 0.683, Ra = 180., Rm = 164e3)
# change passive properties of the axon
# see in Kole et al., 2008
for axon in mycell.axon:
axon.g_pas = 1/15e3
axon.Ra = 50.
axon.cm = 0.9
# homogeneous somatic distribution of Na and K
mycell.active(gnabar_hh = 0.17)
# different distribution of Na and K in dendrites
mycell.active.activatedendrites(fapical, fbasal)
# change active properties of the axon
# see in Kole et al., 2008
for axon in mycell.axon:
axon.insert('hh')
axon.gnabar_hh = 0.250
return mycell
def create_neuron():
""" creates an active neuron, with sigmoid decay of gnabar_hh
in the dendrites """
neuron = Neuron(ApicalBasalActive)
# ** Passive
Passive(neuron)
# see in Kole et al., 2008
for axon in neuron.axon:
axon.g_pas = 1 / 15e3
axon.Ra = 100.0
axon.cm = 0.9
# ** Active
# Active properties in Soma
neuron.soma.gnabar_hh = 0.040
# active custom-distribution of Na and K
h.distance(sec=neuron.soma)
neuron.get_Active().activatedendrites(fsec_apical, fsec_basal)
# change active properties of the axon
# see in Kole et al., 2008
for axon in neuron.axon:
axon.insert("hh")
axon.gnabar_hh = 0.250
return neuron
def inv_sigmoid(x, Vo, plateau, d50, p):
""" inverse sigmoid equation, x is distance """
return ((Vo-plateau)-(Vo-plateau)/(1+e**(-(x-d50)*p)) ) + plateau
# inv_sigmoid as a function of only distance
fdistance = lambda x:inv_sigmoid(x, Vo=0.8, plateau=0.01, d50=110., p=0.04)
# let fdistance to take the segment as an argument
fsec_apical = lambda section : fdistance( h.distance(0, sec=section) )
#fsec_basal = lambda sec: 0.01
fsec_basal = lambda sec: 0.02
# morphology and biophysics
neuron = Neuron(ApicalBasalActive)
h.distance(sec=neuron.soma)
neuron.get_Active().activatedendrites(fsec_apical, fsec_basal)
neuron.soma.gnabar_hh = 0.0
#=========================================================================
# Instrumentation: current injection
#=========================================================================
stim = h.IClamp(0.5, sec = neuron.dend[112])
stim.delay = 2
stim.dur = 0.3
stim.amp = 0.5
#=========================================================================
# Recording: AP waveforms from soma and apical dendrite