A Computational Model of the Temperature-dependent Changes in Firing Patterns in Aplysia Neurons.
10.4196/kjpp.2011.15.6.371
- Author:
Nam Gyu HYUN
1
;
Kwang Ho HYUN
;
Kwang Beom HYUN
;
Jin Hee HAN
;
Kyungmin LEE
;
Bong Kiun KAANG
Author Information
1. Department of Physics, Jeju National University, Jeju 690-756, Korea. nhyun@jejunu.ac.kr
- Publication Type:Original Article
- Keywords:
Aplysia;
Bursting;
Doublet;
Temperature-dependent scaling factor;
Computer simulation
- MeSH:
Aplysia;
Computer Simulation;
Fires;
Neurons;
Potassium;
Potassium Channel Blockers;
Potassium Channels;
Relaxation
- From:The Korean Journal of Physiology and Pharmacology
2011;15(6):371-382
- CountryRepublic of Korea
- Language:English
-
Abstract:
We performed experiments using Aplysia neurons to identify the mechanism underlying the changes in the firing patterns in response to temperature changes. When the temperature was gradually increased from 11degrees C to 31degrees C the firing patterns changed sequentially from the silent state to beating, doublets, beating-chaos, bursting-chaos, square-wave bursting, and bursting-oscillation patterns. When the temperature was decreased over the same temperature range, these sequential changes in the firing patterns reappeared in reverse order. To simulate this entire range of spiking patterns we modified nonlinear differential equations that Chay and Lee made using temperature-dependent scaling factors. To refine the equations, we also analyzed the spike pattern changes in the presence of potassium channel blockers. Based on the solutions of these equations and potassium channel blocker experiments, we found that, as temperature increases, the maximum value of the potassium channel relaxation time constant, taun(t) increases, but the maximum value of the probabilities of openings for activation of the potassium channels, n(t) decreases. Accordingly, the voltage-dependent potassium current is likely to play a leading role in the temperature-dependent changes in the firing patterns in Aplysia neurons.
