$\mathrm{Cc}=\frac{1}{\mathrm{Vc}\times 6.022E2}\mathrm{Cp}=\frac{1}{\mathrm{Vc}\mathrm{Rpc}}\mathrm{Cpc}=\frac{\mathrm{Cc}}{\mathrm{Cp}}\frac{d P}{d t}}=\mathrm{J13}-\mathrm{J9}+\mathrm{J8}\frac{d \mathrm{Pg}}{d t}}=\mathrm{J9}-\mathrm{J11}+\mathrm{J13}\frac{d \mathrm{Pc}}{d t}}=\mathrm{J8}+\mathrm{J12}-\mathrm{J10}\frac{d \mathrm{Pcg}}{d t}}=\mathrm{J10}+\mathrm{J11}-\mathrm{J12}\mathrm{J13}=\mathrm{kf13}\mathrm{Pg}\mathrm{J12}=\mathrm{kf12}\mathrm{Pcg}\mathrm{kr11}=\mathrm{kf11}\mathrm{Kd11}\mathrm{J11}=\mathrm{kf11}\mathrm{Pg}\mathrm{Ca}-\mathrm{kr11}\mathrm{Pcg}\mathrm{J10}=\mathrm{kf10}\mathrm{Pc}\mathrm{Gt}-\mathrm{kr10}\mathrm{Pcg}\mathrm{J8}=\mathrm{kf8}P\mathrm{Ca}-\mathrm{kr8}\mathrm{Pc}\mathrm{J9}=\mathrm{kf9}P\mathrm{Gt}-\mathrm{kr9}\mathrm{Pg}\mathrm{J16}=\mathrm{kf16}\mathrm{IP3}\mathrm{J14}=\frac{\mathrm{kf14}\mathrm{Pc}\mathrm{PIP2}}{\frac{\mathrm{Km14}}{\mathrm{Cpc}}+\mathrm{PIP2}}\mathrm{J15}=\frac{\mathrm{kf15}\mathrm{Pcg}\mathrm{PIP2}}{\frac{\mathrm{Km15}}{\mathrm{Cpc}}+\mathrm{PIP2}}\frac{d \mathrm{IP3}}{d t}}=\mathrm{Cpc}(\mathrm{J14}+\mathrm{J15})-\mathrm{J16}\frac{d \mathrm{Gd}}{d t}}=\mathrm{J7}+\mathrm{J13}+\mathrm{J12}-\mathrm{J2}+\mathrm{J3}\frac{d \mathrm{Gt}}{d t}}=\mathrm{J6}-\mathrm{J7}+\mathrm{J9}+\mathrm{J10}\mathrm{J7}=\mathrm{kf7}\mathrm{Gt}\frac{d \mathrm{Ca}}{d t}}=\mathrm{Cpc}-1(\mathrm{J8}+\mathrm{J11})L=\begin{cases}\frac{\mathrm{Ls}}{1+e^{-80(t-\mathrm{ts}-0.05)}} & \text{if (t< \mathrm{ts}+0.15)\land (t\ge \mathrm{ts})}\\ \mathrm{Ls} & \text{if t\ge \mathrm{ts}+0.15}\\ 0 & \text{otherwise}\end{cases}\mathrm{kr1}=\mathrm{kf1}\mathrm{Kd1}\mathrm{J1}=\mathrm{kf1}RL-\mathrm{kr1}\mathrm{Rl}\mathrm{kr2}=\mathrm{kf2}\mathrm{Kd2}\mathrm{J2}=\mathrm{kf2}R\mathrm{Gd}-\mathrm{kr2}\mathrm{Rg}\frac{d R}{d t}}=-1(\mathrm{J1}+\mathrm{J2})\mathrm{J3}=\mathrm{kf3}\mathrm{Rl}\mathrm{Gd}-\mathrm{kr3}\mathrm{Rlg}\frac{d \mathrm{Rl}}{d t}}=\mathrm{J1}+\mathrm{J6}-\mathrm{J3}\mathrm{kr4}=\mathrm{kf4}\mathrm{Kd4}\mathrm{J4}=\mathrm{kf4}L\mathrm{Rg}-\mathrm{kr4}\mathrm{Rlg}\frac{d \mathrm{Rg}}{d t}}=\mathrm{J2}-\mathrm{J4}\mathrm{J5}=\mathrm{kf5}\mathrm{Rlg}\frac{d \mathrm{Rlgp}}{d t}}=\mathrm{J5}\mathrm{J6}=\mathrm{kf6}\mathrm{Rlg}\frac{d \mathrm{Rlg}}{d t}}=\mathrm{J3}-\mathrm{J5}+\mathrm{J4}-\mathrm{J6}$ Reaction R1 forward rate constant Reaction R9 forward rate constant Receptor not bound to G-alpha-GDP Area density of noncoupled receptors PLC-beta bound to calcium (2+) Binding of calcium to PLC-beta Reaction R8 flux G-alpha-GTP density Reaction R2 forward rate constant PLC-beta bound to G-alpha-GTP Binding of PLC-beta to G-alpha-GTP Reaction R9 flux Density of PLC-beta bound to calcium (2+) Receptor bound to G-alpha-GDP Density of receptors coupled with G-proteins Ligand bound to phosphorylated receptor and G-alpha-GDP Phosphorylated receptor density PIP2 density Ligand bound to receptor Ligand bound to receptor and G-alpha-GDP Dissociation of G-alpha-GTP from activated receptor Reaction R6 flux Time domain Reverse rate constant for the binding of calcium to PLC-beta Degradation of G-alpha-GTP Reaction R7 flux Degradation of free IP3 Reaction R16 flux Reaction R11 dissociation rate constant Reaction R2 reverse rate constant Factor for converting number of particles to a density on the cell�s plasma membrane Reaction R15 Km value Ligand-bound receptor density Full-strength ligand concentration during stimulation PLC-beta bound to calcium (2+) and G-alpha-GTP Density of PLC-beta bound to calcium (2+) and G-alpha-GTP Reaction R14 Km value Hydrolysis of PIP2 by calcium-bound PLC-beta Reaction R14 flux Density of PLC-beta bound to G-alpha-GTP Reaction R2 reverse rate constant Cytosolic volume IP3 concentration in cytosol Hydrolysis of PIP2 by calcium-bound PLC-beta and G-alpha-GTP complex Reaction R15 flux Area density of free inactive G-protein. "...represents the densities of a species required to form that mobile messenger�the amount of free G-alpha-GDP." Reaction R3 reverse rate constant Dissociation of G-alpha-GTP from calcium-bound PLC-beta and degradation Reaction R12 flux Reaction R9 forward rate constant Reaction R10 reverse rate constant Dissociation constant for the binding of ligand to the receptor with attached G-protein Rate constant for the nonstimulated IP3 production reaction Dissociation of G-alpha-GTP from PLC-beta and degradation Reaction R13 flux Active receptor density Binding of ligand to receptor Reaction R1 flux Reaction R1 reverse rate constant Reaction R13 forward rate constant Binding of G-alpha-GTP to calcium-bound PLC-beta Reaction R10 flux Reaction R7 forward rate constant Time of ligand stimulation .1 10000 100 Signal Transduction keyword Cooling Mike m.cooling@auckland.ac.nz Auckland Bioengineering Institute University of Auckland Hunter Peter p.hunter@auckland.ac.nz Auckland Bioengineering Institute University of Auckland Crampin Edmund e.crampin@auckland.ac.nz Auckland Bioengineering Institute University of Auckland 93 Modeling hypertrophic IP3 transients in the cardiac myocyte Biophysical Journal 2007-00-00 00:00 3421 3433 Cytosolic calcium (2+) concentration Extracellular ligand concentration for unstimulated condition Dissociation constant for the binding of unbound receptor to G-protein Rate constant for the degradation of IP3 Factor for converting between density fluxes and concentration fluxes Forward rate constant for the binding of calcium to PLC-beta Binding of calcium to G-alpha-GTP-bound PLC-beta Reaction R11 flux Reaction R11 reverse rate constant Factor for converting from number of particles to cytosolic concentration Reaction R15 forward rate constant Rate constant for the phosphorylation of active receptor Cooling Mike m.cooling@auckland.ac.nz The University of Auckland Auckland Bioengineering Institute Reaction R10 forward rate constant Binding of ligand to receptor and G-alpha-GDP Reaction R4 flux G-protein dissociation rate from the activated receptor Phosphorylation of ligand-bound receptor Reaction R5 flux Dissociation constant for the binding of ligand to the receptor with no attached G-protein Reaction R3 forward rate constant Binding of G-alpha-GDP to receptor Reaction R2 flux PLC-beta density Reaction R12 forward rate constant Ratio of plasma membrane surface area to cytosolic volume Forward rate for the binding of ligand to precoupled receptor Reaction R11 forward rate constant Binding of ligand and receptor to G-alpha-GDP Reaction R3 flux