Table 1.
Parameters for simulations of 1 and 2 compartment models
| 2 Compartment Model |
||||
|---|---|---|---|---|
| Parameter | 1 Compartment Model | Compartment 1 | Compartment 2 | Parameter Definition |
| Vpipette, pl | 4 × 104 | 4 × 104 | Pipette volume (29, 30) | |
| V, pl | 2.048 | 0.048 | 2 | Compartment volume (29, 30) |
| J2/3, l/s | 1.6 × 10−13 | N/A | 1.6 × 10−13 | Flux coefficient from pipette to cytosol (29, 30) |
| J1/2, l/s | N/A | 1.6 × 10−16 | N/A | Flux coefficient from compartment 1 to compartment 2† (29, 30) |
| EPDE4:Ci, μM/s | 0.42 | 0.021 | 0.42 | Maximal hydrolysis rate for PDE4 in indicated compartment*† |
| Km-PDE4, μM | 3 | 3 | 3 | Michaelis constant for PDE4*† (10, 16) |
| Ki-PDE4, μM | 0.2 | 0.2 | 0.2 | Inhibition constant for PDE4 (10, 16) |
| EPDE8MM:Ci, μM/s | 0.17 | 0 | 0.17 | Maximal hydrolysis rate for 8MM-IBMX sensitive PDE in indicated compartment*† |
| Km-PDE8MM, μM | 1 | N/A | 1 | Michaelis constant of 8MM-IBMX sensitive PDE* |
| Ki-PDE8MM, μM | 5 | N/A | 5 | Inhibition constant of 8MM-IBMX-sensitive PDE (1, 31) |
| K1/2, μM | 1 or 40 (as indicated) | 1 or 40 (as indicated) | N/A | [cAMP] at which 50% of CNG channels are active (29–31) |
| N | 2 | 2 | N/A | Hill coefficient for CNG channel activation (29–31) |
PDE, phosphodiesterase; CNG, cyclic nucleotide gated; 8MM-IBMX, 8-methoxymethyl IBMX.
*
Parameters were measured experimentally.
†
Parameters were manually fit to data.