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🔴 Presynaptic Terminal
Axon Terminal Button
Terminal Membrane Potential
-70mV
Resting
Ca²⁺ Channels 0 / 12 open
Intracellular [Ca²⁺] 100 nM
CB1 Receptors Inactive
Release Probability 15%
Vesicle Pools
RRP: 10
Recycling: 50
Reserve: 200
SNARE Complex Status
Synaptobrevin Syntaxin SNAP-25
Primed - Awaiting Ca²⁺
🔵 Postsynaptic Spine
Dendritic Spine
Spine Membrane Potential
-70mV
Resting
EPSP: 0 mV
IPSP: 0 mV
Ionotropic Receptors
AMPA 0/8 bound
NMDA 0/6 bound (Mg²⁺ block)
GABA-A 0/4 bound
Metabotropic Receptors
mGluR Inactive
GABA-B Inactive
G-protein cascade: Idle
🧠 Synaptic Plasticity
AMPA: 100%
🌿 Endocannabinoid System
2-AG synthesis: Low
Retrograde signal: None
⚡ Synaptic Cleft
Width: ~15 nm
Glutamate: 0
GABA: 0
Free ions: Na⁺ K⁺ Cl⁻
Clearance Mechanisms
Reuptake (EAAT): Active
Enzymatic: AChE ready
Astrocyte uptake: Active
Molecular Components
Synaptic Vesicle
Glutamate
GABA
Ca²⁺
Na⁺
K⁺
Cl⁻
2-AG / Anandamide
AMPA Receptor
NMDA Receptor
CB1 Receptor
Astrocyte End-feet
Structures
Terminal Dome
Pre Membrane (face)
Spine Dome
Post Membrane (face)
Ca²⁺ Channel
Active Zone / PSD
🖱️ Click terminal to trigger AP • Scroll to zoom • Drag to rotate • Drag panel headers to move • Click − to minimize

Synaptic Controls

AP Frequency (Hz) 10 Hz

🧬 Neurotransmitter Type

Vesicle NT Content ~5000

⚙️ Presynaptic Modulation

Ca²⁺ Channel Density 100%
Release Probability (Pr) 0.15
CB1 Activation Level 0%
↑ Reduces release probability (DSI)

🔬 Postsynaptic

AMPA Receptor Density 100%
NMDA Mg²⁺ Block 100%
↓ Simulates depolarization relief
Endocannabinoid Synthesis
Enables retrograde signaling

🌟 Visualization

Animation Speed 1.0x

👁️ Structure Visibility

Toggle to identify structures
🔴 ALL Presynaptic
🔵 ALL Postsynaptic
⭕ Membrane Only Mode
Hides domes, shows only membrane faces
Ca²⁺ Channels
Vesicles
Astrocyte End-feet
Ion Flow Particles
Synaptic Transmission:
• AP arrives → Ca²⁺ channels open
• Ca²⁺ influx → synaptotagmin binding
• SNARE zippering → vesicle fusion
• NT release (exocytosis) → cleft
• Receptor binding → ion flux
• EPSP/IPSP → postsynaptic potential

Retrograde Signaling:
• Strong activation → eCB synthesis
• 2-AG → CB1 receptors (presynaptic)
• ↓ Ca²⁺ influx → ↓ release (DSI/DSE)
FPS: 60
Vesicles Released: 0
Total EPSPs: 0
Sim Time: 0.00 ms
Presynaptic Voltage & Ca²⁺
━ Vm ━ [Ca²⁺]
Postsynaptic Potential
━ PSP ┄ Threshold
Cleft [NT] & Receptor Binding
━ [NT] ━ Binding
Ion Flow (Influx/Efflux)
━ Net ━ Na⁺ ━ K⁺ ━ Cl⁻
🧠 Synaptic Plasticity (LTP/LTD)
Spine [Ca²⁺]
0.00
AMPA Strength
100%
State: Baseline
Signaling Cascade:
Ca²⁺/CaM → CaMKII: 0%
Ca²⁺ → Calcineurin: 0%
AMPA trafficking: 0
Net AMPA density: 100%
Plasticity Effect on Binding & Current
AMPA density Binding Current
LTP: High Ca²⁺ → CaMKII → ↑AMPA
LTD: Mod Ca²⁺ → Calcineurin → ↓AMPA