|
Symbol | Description | Range | Value | Units |
|
Synaptic dynamics |
| Depression time constant | >0.01–2 | s.s. | s |
| Facilitation time constant | >0.5–2 | s.s. | s |
| Resting synaptic release probability | <0.09–0.9 | s.s. | — |
|
Neurotransmitter release and time course |
| Total vesicular glutamate concentration | 300–1000 | 500 | mM |
| Vesicular versus mixing volume ratio | | 0.005 | — |
| Glutamate clearance time constant | 2–100 | 25 | ms |
| Efficacy of synaptic transmission | 0-1 | 0.75 | — |
|
Astrocyte GPCR kinetics |
| Agonist binding rate | | 0.3 | M−1s−1 |
| Agonist unbinding time | | 0.55 | s |
|
IP3R kinetics |
| Inact. Ca2+ binding rate (with Ca2+ act.) | 0.04–0.18 | 0.2 | M−1s−1 |
| IP3 binding affinity | 0.1–0.15 | 0.13 | M |
| Inact. Ca2+ binding affinity (Ca2+ act.) | | 1.05 | M |
| IP3 binding affinity (Ca2+ inact.) | | 0.9434 | M |
| Act. Ca2+ binding affinity | | 0.08 | M |
|
Calcium fluxes |
| ER-to-cytoplasm volume ratio | 0.4–0.7 | 0.18 | — |
| Total ER Ca2+ content | 3–5 | 2 | M |
| Max. Ca2+ leak rate | 0.05–0.1 | 0.1 | s−1 |
| Max. Ca2+ release rate by IP3Rs | >6 | 6 | s−1 |
| Ca2+ affinity of SERCA pumps | 0.05–0.1 | 0.05 | M |
| Max. Ca2+ uptake rate | 0.4–1.3 | 0.9 | M s−1 |
|
IP3 production |
| Max. rate of IP3 production by PLC | 0.05–2 | 1 | M s−1 |
| Ca2+ affinity of PLC | 0.1–1 | 0.5 | M |
| Inhibiting IP3 affinity of PLC | 1–1.5 | 1 | M |
| Max. rate of IP3 production by PLC | <0.8 | 0.05 | M s−1 |
|
IP3 degradation |
| Max. rate of IP3 degradation by IP-5P | >0.05–0.25 | 0.1 | s−1 |
| Ca2+ affinity of IP3-3K | 0.4–0.5 | 0.5 | M |
| IP3 affinity of IP3-3K | 0.7–1 | 1 | M |
| Max. rate of IP3 degradation by IP3-3K | >0.6 | 4.5 | M s−1 |
|
Gliotransmitter release and time course |
| Ca2+ threshold for exocytosis | 0.15–0.8 | 0.5 | M |
| Glutamate recycling time constant | 0.003–1.5 | 1.66 | s |
| Resting glutamate release probability | <0.9 | 0.6 | — |
| Vesicular versus mixing volume ratio | | 6.5 ⋅ 10−4 | — |
| Glutamate clearance time constant | ≤300 | 200 | ms |
|
Presynaptic receptors |
| Activation rate | >0.3 | 1.5 | M−1s−1 |
| Inactivation time constant | >30–180 | 120 | s |
| Gliotransmission type | 0-1 | s.s. | — |
|
Postsynaptic neuron |
| Membrane time constant | 20–70 | 40 | ms |
| Refractory period | 1–5 | 2 | ms |
| Resting potential | −78.2–−54.8 | −60 | mV |
| Firing threshold | −55–−51 | −55 | mV |
| Reset potential | −58–−53 | −57 | mV |
| Peak AP amplitude | 29.8–41.2 | 30 | mV |
| Input resistance | 60–150 | s.s. | M |
|
Postsynaptic currents |
| EPSC rise time | 0.4–0.6 | 0.5 | ms |
| EPSC decay time | 2.7–11.6 | 10 | ms |
| Synaptic efficacy | | 4.3 | — |
| EPSP amplitude | 0.5–7.5 | 2 | mV |
|
Slow inward currents |
| SIC rise time | 20–70 | 20 | ms |
| SIC decay time | 100–800 | 600 | ms |
| SIC efficacy | | 68 | — |
| SIC amplitude | 1–10 | 4.5 | mV |
|
Spike-timing-dependent plasticity |
| NMDAR-mediated Ca2+ increase per AP | | 1.0 | — |
| NMDAR Ca2+ rise time | | 10 | ms |
| NMDAR Ca2+ decay time | | 30 | ms |
| Synaptic weight | | 39.7 | — |
| VDCC-mediated Ca2+ increase per AP | | 2.5 | — |
| VDCC Ca2+ rise time | | 2 | ms |
| VDCC Ca2+ decay time | | 12 | ms |
| SIC-mediated Ca2+ increase per AP | | 1.0 | — |
| SIC Ca2+ rise time | | 5 | ms |
| SIC Ca2+ decay time | | 100 | ms |
| SIC weight | | 10.6 | — |
| Amplification of NMDAR-mediated Ca2+ | | 4 | — |
| LTD threshold | | 1.0 | — |
| LTP threshold | | 2.2 | — |
| LTD learning rate | | 0.57 | s−1 |
| LTP learning rate | | 2.32 | s−1 |
| Boundary between UP/DOWN states | | 0.5 | — |
| Decay time of synaptic change | | 1.5 | s |
| Noise amplitude | | 0.1 | — |
| Fraction of synapses in the DOWN state | | 0.5 | — |
| UP/DOWN Synaptic strength ratio | | 4 | — |
|