1. A Computational model of the mammalian external tufted cell
- Author
-
Alla Borisyuk and Ryan Viertel
- Subjects
0301 basic medicine ,Statistics and Probability ,Population ,Action Potentials ,Synaptic Transmission ,General Biochemistry, Genetics and Molecular Biology ,Membrane Potentials ,Synchronization (alternating current) ,03 medical and health sciences ,Bursting ,0302 clinical medicine ,medicine ,Animals ,Humans ,Computer Simulation ,Sensitivity (control systems) ,education ,Glomerulus (olfaction) ,Physics ,Ions ,Mammals ,education.field_of_study ,General Immunology and Microbiology ,Applied Mathematics ,Depolarization ,General Medicine ,Olfactory Bulb ,Hodgkin–Huxley model ,Smell ,Kinetics ,030104 developmental biology ,medicine.anatomical_structure ,Tufted cell ,Modeling and Simulation ,General Agricultural and Biological Sciences ,Biological system ,030217 neurology & neurosurgery - Abstract
We introduce a novel detailed conductance-based model of the bursting activity in external tufted (ET) cells of the olfactory bulb. We investigate the mechanisms underlying their bursting, and make experimentally-testable predictions. The ionic currents included in the model are specific to ET cells, and their kinetic and other parameters are based on experimental recordings. We validate the model by showing that its bursting characteristics under various conditions (e.g. blocking various currents) are consistent with experimental observations. Further, we identify the bifurcation structure and dynamics that explain bursting behavior. This analysis allows us to make predictions of the response of the cell to current pulses at different burst phases. We find that depolarizing (but not hyperpolarizing) inputs received during the interburst interval can advance burst timing, creating the substrate for synchronization by excitatory connections. It has been hypothesized that such synchronization among the ET cells within one glomerulus might help coordinate the glomerular output. Next we investigate model parameter sensitivity and identify parameters that play the most prominent role in controlling each burst characteristic, such as the burst frequency and duration. Finally, the response of the cell to periodic inputs is examined, reflecting the sniffing-modulated input that these cell receive in vivo. We find that individual cells can be better entrained by inputs with higher, rather than lower, frequencies than the intrinsic bursting frequency of the cell. Nevertheless, a heterogeneous population of ET cells (as may be found in a glomerulus) is able to produce reliable periodic population responses even at lower input frequencies.
- Published
- 2018