Contribution of voltage-dependent potassium channels to the somatic shunt in neck motoneurons of the cat.

@article{Campbell1997ContributionOV,
  title={Contribution of voltage-dependent potassium channels to the somatic shunt in neck motoneurons of the cat.},
  author={D M Campbell and P. Ken Rose},
  journal={Journal of neurophysiology},
  year={1997},
  volume={77 3},
  pages={
          1470-86
        }
}
The specific membrane resistivity of motoneurons at or near the soma (Rms) is much lower than the specific membrane resistivity of the dendritic tree (Rmd). The goal of the present experiments was to investigate the contribution of tonically active voltage-dependent potassium channels at or near the soma to the low Rms. These channels were blocked with the use of intracellular injections of cesium. Input resistance (RN), Rms/Rmd, a conductance representing voltage-dependent potassium channels… 
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TLDR
It might be suggested that the majority of these potassium conductances underlying membrane resistance are initially located in the distal dendrites but become more uniformly distributed over the motoneuron surface in the oldest animals.
Computational estimation of the distribution of L-type Ca(2+) channels in motoneurons based on variable threshold of activation of persistent inward currents.
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It is concluded that the set of L-type Ca(2+) channels mediating plateau potentials is restricted to discrete regions in the dendritic tree, which leads to the compartmentalization of the dendedritic tree of motoneurons into subunits whose sequential activation lead to the graded amplification of synaptic inputs.
Relative location of inhibitory synapses and persistent inward currents determines the magnitude and mode of synaptic amplification in motoneurons.
TLDR
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It is concluded that R(m) is distinct between neuron classes, and generally affects function only in T neurons that integrate multiple subthreshold inputs and are modulated by peptidergic transmitters.
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Voltage recordings from neostriatal projection neurons were obtained using in vitro intracellular techniques before and during K-blockade, suggesting a differential action of different K+-blockers on the somato-dendritic membrane, implying a differential distribution of membrane conductances.
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TLDR
Reconfigurations of the effective dendritic field of the motoneurons are activity‐dependent and geometry‐dependent, demonstrating that the same anatomic structure that shrinks or expands according to the background synaptic activity can select the types of its synaptic inputs.
Estimation of the electrical parameters of spinal motoneurons using impedance measurements.
TLDR
Most motoneuron parameters obtained in somatic shunt and sigmoidal models were well correlated, and parameters were moderately affected by changes in dendritic profile, but voltage-dependent conductances are a substantial component of resting electrical properties.
Role of synaptic inputs in determining input resistance of developing brain stem motoneurons.
TLDR
The fast inhibitory synapses (glycine, GABA(A)) play a greater role in determining cell excitability in developing brain stem motoneurons as postnatal development progresses, and a nonselective distribution of the blocked synaptic conductances over the cell body and dendrites is indicated.
Characteristics and organization of discharge properties in rat hindlimb motoneurons.
The discharge properties of hindlimb motoneurons in ketamine-xylazine anesthetized rats were measured to assess contributions of persistent intrinsic currents to these characteristics and to…
Determination of the location and magnitude of synaptic conductance changes in spinal motoneurons by impedance measurements.
TLDR
This study indicates that location and conductance of tonic dendritic conductances can be estimated from F(r), cuDeltaZ, and basic electrotonic motoneuron parameters with the exercise of suitable precautions.
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