Effects of dendritic properties on the correlations in ionic channels emerging from firing rate homeostasis: a two-compartment modeling study.

Abstract

Homeostatic regulation of firing rate is an important feature of neural excitability, which is achieved through feedback control of diverse ionic channel expression levels. The output firing rate is controlled by the active currents and passive properties of the dendrites. The objective of this study is to determine how dendritic properties affect the homeostatic regulation of somatic firing rate. We used a two-compartment Pinsky-Rinzel model to simulate action potentials in a pyramidal neuron in response to external inputs. We applied a feedback framework to determine the maximum ionic conductances during homeostatic regulation and examined the pairwise correlations among these conductances. We find that the effective regulation of somatic firing rate could be achieved through controlling both somatic and dendritic ionic channels. The correlations among these channels are lower than those emerging from the regulation through the control of somatic or dendritic channels. It is also shown that increasing the number of adjustable channels alters ionic channel correlations when the additional channel has a strong compensatory relationship with other channels. Compared to the coupling conductance between two compartments, varying the proportion of area occupied by the dendrite produces a greater effect on firing rate dynamics and expression correlations between adjustable channels in both dendrite and soma. The results reveal that dendritic ionic channels, morphological feature and dendritic-somatic coupling are all factors that influence the correlations in ionic channel expression. These findings provide a biophysical basis for the relationship between dendritic properties and neuronal information processing.

Supplementary information: The online version contains supplementary material available at 10.1007/s11571-025-10297-z.