TITLE:
Bifurcation Analysis of a Coupled Acetylcholinesterase/Choline Acetyltransferase Enzymes Neurocycle
AUTHORS:
Hamza M. Habib, G. Ibrahim, Osama Noman Saleh
KEYWORDS:
Neurocycle Modelling; Acetylcholinesterase/Choline Acetyltransferase; Bifurcation; Enzyme; Nonlinear Dynamics
JOURNAL NAME:
Advances in Chemical Engineering and Science,
Vol.3 No.1,
January
11,
2013
ABSTRACT:
A diffusion-reaction, two-compartment model was used to explore the
bifurcation and chaotic behavior of acetylcholinesterase (AChE) and
cholineacetyltransferase (ChAT) coupled enzymes system. The effects of hydrogen
ion feed concentrations, choline (Ch) and acetylcholine (ACh) feed
concentrations, as bifurcation parameters on the system performance are
studied. It is found that hydrogen ions play an important role in creating
potential differences through the plasma membranes. Detailed bifurcation
analysis over a wide range of parameters is carried out in order to uncover
some of the qualitative changes of the system such as hysteresis, multiplicity,
Hopf bifurcation, boundary crises bifurcation, periodic transient, and other
complex dynamics. Some of the obtained results relate to the phenomena
occurring in the physiological experiments like periodic stimulation of neural
cells and irregular functioning of acetylcholine receptors. The model depends
on real kinetics expressions and parameters obtained from the literature, so
the results can be used to direct more systematic research on cholinergic
disorder.