The crustacean cardiac ganglion network coordinates rhythmic contractions of the heart muscle to control the circulation of blood. The specific network of the crab (Cancer borealis) comprises nine cells: five large cell motor neurons (LC1-5) and four small endogenous pacemaker cells (SCs). We report a new three-compartmental biophysical LC model that includes synaptic inputs from SCs onto gap-junction coupled spike-initiation-zone (SIZ) compartments. To determine physiologically viable LC models in this realistic configuration, we sampled maximal conductances from a biologically constrained 9-D parameter space, followed by a selection protocol that had three levels. Our results provide previously unknown structure-function insights related to the crustacean cardiac ganglion large cell, including predictions about morphology, SIZ, and the differential roles of active conductances in the three compartments.
Experimental motivation: Conductance correlations exist between mRNA in the C. Borealis pacemaker. This study seeks functional explanations for why correlations between channel conductances my exist.
Model Type: Realistic Network
Region(s) or Organism(s):
Cell Type(s): Heart cell
Currents: I CAN; I Na,p; IK Bkca; IK Skca; I_K,Na; I_KD
Receptors:
Genes:
Transmitters:
Model Concept(s): Cardiac pacemaking; Detailed Neuronal Models
Simulation Environment: NEURON
References:
Dopp DP et al. (2026). Conductance relationships across compartments associated with bursting output in a model of a motor neuron in the crustacean cardiac ganglion. Journal of neurophysiology. 135 [PubMed]