modelCytosol

Extends from BioChem.Compartments.MainCompartment (Main compartment (constant volume)).

Information

Ca Oscillations

This example is a Modelica version of the model presented in A Minimal Generic Model of Bacteria-Induced Intracellular Ca²⁺ Oscillations in Epithelial Cells by Camilla Oxhamre, Agneta Richter-Dahlfors, Vladimir P. Zhdanov, and Bengt Kasemoy. (Biophysical Journal Volume 88 April 2005 2976-2981)

Abstract

The toxin &alpha-hemolysin expressed by uropathogenic Escherichia coli bacteria was recently shown as the first pathophysiologically relevant protein to induce oscillations of the intracellular Ca²⁺ concentration in target cells. Here, we propose a generic three-variable kinetic model describing the Ca²⁺ oscillations induced in single rat renal epithelial cells by this toxin. Specifically, we take into account the interplay between 1), the cytosolic Ca²⁺ concentration; 2), IP₃-sensitive Ca²⁺ channels located in the membrane separating the cytosol and endoplasmic reticulum; and 3), toxin-related activation of production of IP₃ by phospholipase C. With these ingredients, the predicted response of cells exposed to the toxin is in good agreement with the results of experiments.

Simulations

The simulation results are shown in the Figure 1. This plot corresponds to Fig 1C of the paper (Oxhamre 2005).
Fig1: Simulation results

Parameters

Type	Name	Default
Real	n0	1
Real	kbN	0.5
Real	kappa	5
Real	p11	0.2
Real	p12	0.8
Real	K1	5
Real	K2	0.7
Real	k31	0.5
Real	K3	0.7

Components

Type	Name	Default	Description
BioChem.Units.Volume	V (from Compartment)		Compartment volume
Endoplasmic_Reticulum	endoplasmicReticulum
Real	Cytosol_V	V	Variable used to make the compartment volume accessible for inner components. Do not edit.
Real	Endoplasmic_Reticulum_V	endoplasmicReticulum.V	Variable used to make the compartment volume of inner compartments accessible. Do not edit.
Cytosol.Ca_Cyt_	Ca_Cyt
Real	n_sbml
Real	p1_sbml
Real	p2_sbml
Real	p3_sbml
Cytosol.Jpump_	Jpump

Name	Description
Ca_Cyt_
Jpump_