These are the NEURON files for modelling a tonic neuron from the
Dorsal Reticular Nucleus (DRt), based on the experimental voltage
traces. This model was used for:
1) recreating the firing properties of DRt neurons;
2) studying the possible membrane currents giving rise to the
after-hyperpolarization variability observed experimentally;
3) exploring the mechanisms shaping the membrane potential histograms
under spontaneous activity conditions.
The Hodgkin-Huxley formalism was used to describe the ionic currents
present in the model: a persistent sodium current (INa), a
delayed-rectifier potassium current (IKdr), a voltage dependent
calcium current (ICa, L-type high threshold), and a calcium activated
potassium current (IK,Ca, or IAHP given its role in shaping the
The model also included a description for the internal calcium
concentration dynamics. Synapses were modelled using dual exponential
conductance profiles and were introduced for the sole purpose of
introducing and analysing the contribution of membrane
fluctuations. The parametrization of the synaptic inputs was set in
order to produce a zero net change in membrane potential. Stochastic
network activity was simulated by adding random excitatory and
inhibitory synaptic inputs with predefined mean times. Membrane
potential fluctuations were generated by injecting normally
distributed current noise to the neuron model.
This model is described in:
Sousa M., Szucs P, Lima D. and Aguiar P. "The pronociceptive dorsal
reticular nucleus contains mostly tonic neurons and shows a high
prevalence of spontaneous activity in block preparation". Accepted at
Journal of Neurophysiology, January 2014.
Core model parameters are specified in the Appendix section.
Mafalda Sousa and Paulo Aguiar
contact email: firstname.lastname@example.org and email@example.com