Role of TRP channels in dendritic integration and subthreshold membrane potential plateaus
© Petersson and Fransén; licensee BioMed Central Ltd. 2011
Published: 18 July 2011
Cortical as well as subcortical neurons display plateau properties . The plateaus may be voltage and/or calcium gated and depend on Na, Ca or mixed cation (TRP) currents. Depending on the nature of the synaptic input, neurons may respond by entering one of several multiple stable states, in the form of either subthreshold or persistent firing. We have studied the activation of a TRP current, in which synaptic excitatory input activates metabotropic glutamate receptors in turn leading to a TRP-mediated slow EPSP, both experimentally  and computationally . In the computational work we have studied the contribution of the TRP current on dendritic integration of input of low (1-10 Hz) frequency.
The model is based on a CA1 pyramidal cell model  developed to study dendritic processing. The spatial compartmentalization had been obtained from a digitized neuron and contains 183 compartments. It includes ion channels described by a Hodgkin-Huxley formalism and has the following channels: Na, NaP, CaR, CaT, CaL, Kdr, KA, KM, K(Ca)BK, K(Ca)slow, Kleak, h. To this model we added models for a metabotropic glutamate receptor as well as a TRP channel, the latter being adapted from a CAN channel model.
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