TY - JOUR
T1 - Control of firing patterns by two transient potassium currents
T2 - Leading spike, latency, bistability
AU - Meng, Xiangying
AU - Lu, Qishao
AU - Rinzel, John
N1 - Funding Information:
Acknowledgements The research for this study was supported in part for JR, XYM by the National Institutes of Health grant DC008543-01 and for QL, XYM by the National Natural Science Foundation of China grants 10872014, 10702002, 10802012 and 10902001. JR and XYM thank M. Remme and P. Manis for helpful discussions during the course of this work and B. Clark for comments on the manuscript. We thank the TNList of Tsinghua University for hospitality during part of this work.
PY - 2011/8
Y1 - 2011/8
N2 - Transient potassium currents distinctively affect firing properties, particularly in regulating the latency before repetitive firing. Pyramidal cells of the dorsal cochlear nucleus (DCN) have two transient potassium currents, I Kif and I Kis, fast and slowly inactivating, respectively, and they exhibit firing patterns with dramatically variable latencies. They show immediate repetitive firing, or only after a long latency with or without a leading spike, the so-called pauser and buildup patterns. We consider a conductance-based, ten-variable, single-compartment model for the DCN pyramidal cells (Kanold and Manis 2001). We develop and analyze a reduced three-variable integrate-and-fire model (KM-LIF) which captures the qualitative firing features. We apply dynamical systems methods to explain the underlying biophysical and mathematical mechanisms for the firing behaviors, including the characteristic firing patterns, the latency phase, the onset of repetitive firing, and some discontinuities in the timing of latency duration (e.i. first spike latency and first inter spike interval). Moreover, we obtain new insights associated with the leading spike by phase plane analysis. We further demonstrate the effects of possible heterogeneity of I Kis. The latency before repetitive firing can be controlled to cover a large range by tuning of the relative amounts of I Kif and I Kis. Finally, we find for the full system robust bistability when enough I Kis is present.
AB - Transient potassium currents distinctively affect firing properties, particularly in regulating the latency before repetitive firing. Pyramidal cells of the dorsal cochlear nucleus (DCN) have two transient potassium currents, I Kif and I Kis, fast and slowly inactivating, respectively, and they exhibit firing patterns with dramatically variable latencies. They show immediate repetitive firing, or only after a long latency with or without a leading spike, the so-called pauser and buildup patterns. We consider a conductance-based, ten-variable, single-compartment model for the DCN pyramidal cells (Kanold and Manis 2001). We develop and analyze a reduced three-variable integrate-and-fire model (KM-LIF) which captures the qualitative firing features. We apply dynamical systems methods to explain the underlying biophysical and mathematical mechanisms for the firing behaviors, including the characteristic firing patterns, the latency phase, the onset of repetitive firing, and some discontinuities in the timing of latency duration (e.i. first spike latency and first inter spike interval). Moreover, we obtain new insights associated with the leading spike by phase plane analysis. We further demonstrate the effects of possible heterogeneity of I Kis. The latency before repetitive firing can be controlled to cover a large range by tuning of the relative amounts of I Kif and I Kis. Finally, we find for the full system robust bistability when enough I Kis is present.
KW - A-type current
KW - Bistability
KW - Dynamics
KW - Firing
KW - Latency
UR - http://www.scopus.com/inward/record.url?scp=80052459868&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80052459868&partnerID=8YFLogxK
U2 - 10.1007/s10827-010-0297-5
DO - 10.1007/s10827-010-0297-5
M3 - Article
C2 - 21181249
AN - SCOPUS:80052459868
SN - 0929-5313
VL - 31
SP - 117
EP - 136
JO - Journal of Computational Neuroscience
JF - Journal of Computational Neuroscience
IS - 1
ER -