This code is a Hodgkin-Huxley type model of parvalbumin-expressing interneurons (PVINs) in the dorsal horn of the spinal cord. This model is adopted from Bischop et al. 2012 and reparametrized to fit the electrical activity of spinal dorsal horn PVINs from naive mice. It reproduces the firing behavior change from tonic to transient observed in PVINs following nerve injury, which is achieved by a reduction in cytosolic calcium buffer concentration. The bifurcation analysis of PVIN model further explains how the firing pattern transits as the injection current increases, in a manner similar to that seen in our transient firing PVIN recordings. The code also includes an “in vivo-like” neural circuit model of Aß fiber-mediate nociceptive neural circuit. The circuit model is stimulated by Poisson-distributed excitatory synaptic currents representing the presynaptic inputs from the Aß fibers. It includes the PVIN model above and another HH type model describing the excitability of a PVIN post-synaptic target: the excitatory interneuron expressing protein kinase C gamma (PKCgIN). The Aß fiber-like presynaptic current was applied on both the inhibitory PVIN model and the excitatory PKCgIN model, the latter of which also received inhibitory synaptic input from the PVIN model.
Model Type: Neuron or other electrically excitable cell
Cell Type(s): Spinal cord lamina I-III interneuron
Ma X, Miraucourt L, Qiu H, Sharif-Naeini R, Khadra A. (). Modulation of SK channels via calcium buffering tunes intrinsic excitability of parvalbumin interneurons in neuropathic pain: A computational and experimental investigation J Neurosci.