The present study investigated how the modulation of these currents altered the spike duration and excitability of sensory neurons and examined the relative contributions of PKA- and PKC-mediated effects to the actions of 5-HT. A Hodgkin-Huxley type model was developed that described the ionic conductances in the somata of sensory neurons. The descriptions of these currents and their modulation were based largely on voltageclamp data from sensory neurons. Simulations were preformed with the program SNNAP (Simulator for Neural Networks and Action Potentials). The model was sufficient to replicate empirical data that describes the membrane currents, action potential waveform and excitability as well as their modulation by application of 5-HT, increased levels of adenosine cyclic monophosphate or application of active phorbol esters. The results provide several predictions that warrant additional experimental investigation and illustrate the importance of considering indirect as well as direct effects of modulatory agents on the modulation of membrane currents. See paper for more details.
Model Type: Neuron or other electrically excitable cell
Cell Type(s): Aplysia sensory neuron
Currents: I Na,t; I A; I K; I K,Ca; I CAN; I Potassium
Transmitters: Serotonin
Model Concept(s): Action Potentials; Invertebrate
Simulation Environment: SNNAP
Implementer(s): Baxter, Douglas
References:
Baxter DA, Canavier CC, Clark JW, Byrne JH. (1999). Computational model of the serotonergic modulation of sensory neurons in Aplysia. Journal of neurophysiology. 82 [PubMed]