Premium
A Preliminary Ionic Current Model for Central Chemosensitive Neurons
Author(s) -
Quintero Maria,
Cordovez Juan,
Putnam Robert
Publication year - 2015
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.29.1_supplement.860.11
Subject(s) - neuroscience , depolarization , neuronal firing , brainstem , neuron , chemistry , respiratory system , membrane potential , bursting , biophysics , electrophysiology , biology , anatomy
Although the magnitude of the firing rate response of chemosensitive neurons to increased CO 2 /H + has been associated primarily with accelerating pathways, recent studies have suggested that an additional braking pathway related with multiple factors can also limit the effect of neuronal responses to CO 2. Such a braking pathway is thought to be driven by a hyperpolarizing effect that limits the sensitivity of the cell. In a previous study we have investigated the role of both pathways in the magnitude of the firing rate response in individual neurons using a computational model of single respiratory neurons based on the Hodgkin‐Huxley formulation. That model resulted in a larger hypercapnic‐induced firing rate response after inhibition of the braking pathway but its behavior did not completely agree with the rhythm and pattern that characterizes chemosensitive respiratory neurons. In this study we developed a more physiologically realistic model that includes a set of pH‐ and Ca 2+ ‐sensitive K + currents and reproduces the behavior of respiratory neurons. Our simulations show that both the inhibition of acid‐sensitive depolarizing currents, as well as the release from inhibition of a hyperpolarizing current, play a significant role on the increased firing rate response of the neuron to increased acidotic conditions. We consider that this model is a potentially useful adjunct for on‐going research into the braking pathways involved in the chemosensitive response of neurons from different nuclei in the brainstem.