|
|
||||||||
NEUROREGULATION AND MOTILITY
Department of Zoology, University of Melbourne, Victoria 3010, Australia
Submitted 27 March 2003 ; accepted in final form 28 May 2003
Regenerative potentials evoked by intracellular current injection in single bundles of circular smooth muscle taken from guinea pig antrum have the characteristics of the secondary regenerative component of the slow wave occurring in the same muscle layer. Such regenerative depolarizations might result from a mechanism that responds to membrane polarization with a delayed increase in the rate of production of unitary potentials detected in this tissue. To test this possibility, a two-stage reaction leading to the formation of an intracellular messenger was proposed. The first forward reaction was voltage-dependent, in the manner described by the Hodgkin-Huxley transient Na conductance formalism, allowing simulation of anode break excitation, stimulus threshold strength-duration characteristics, and refractory behavior. A conventional dose-effect relationship was proposed to describe the dependence of the mean rate of discharge of unitary potentials on messenger concentration. Unitary potentials were modeled as unitary membrane conductance modulations with an empirically derived amplitude distribution and Poisson-distributed intervals. The model reproduces a range of spontaneous and evoked membrane potential changes characteristic of antral circular muscle bundles.
mathematical model; stomach; slow wave; interstitial cells of Cajal; inositol 1,4,5-trisphosphate
This article has been cited by other articles:
![]() |
R. A. Faville, A. J. Pullan, K. M Sanders, and N. P. Smith A Biophysically Based Mathematical Model of Unitary Potential Activity in Interstitial Cells of Cajal Biophys. J., July 1, 2008; 95(1): 88 - 104. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. McDonnell, R. Hamilton, M. Fong, S. M. Ward, and K. D. Keef Functional evidence for purinergic inhibitory neuromuscular transmission in the mouse internal anal sphincter Am J Physiol Gastrointest Liver Physiol, April 1, 2008; 294(4): G1041 - G1051. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |