# postsynapse.md Qui comprendiamo: - POSTSYNAPSE: Postsynapse - POST-AMPA: AMPA receptors (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors) ## POSTSYNAPSE: Container **Simplified Behaviors**: — ms: - NT arrives in cleft → AMPA receptors bind NT (receptor availability constant, no desensitization) - V_post rises with AMPA conductance, decays passively each ms - bAP arrives → V_post receives additional depolarisation boost - NMDA gate checks coincidence: NT_cleft AND V_post both non-zero - Mg_block_removal = V_post / (V_post + V_NMDA_half) — sigmoid of V_post - Ca²⁺ enters spine via NMDA: Ca_post += k_NMDA × NT_cleft × Mg_block_removal - Ca_post decays slowly each ms (single exponential, no pump detail) - Ca_post_history updated every ms (feeds seconds loop) - V_post_history updated every ms (retained for reference) — seconds: - Ca_post_history mean computed over past 2 s - eCB synthesised when Ca_post_history mean exceeds eCB threshold - eCB_level decays when Ca_post_history mean falls below threshold - eCB_level written → read by presynapse as retrograde brake on VGCCs - Ca_post_history compared to LTP/LTD thresholds → plasticity tag set — mins: - If Plasticity_LTP tagged → AMPA density increases - If Plasticity_LTD tagged → AMPA density decreases - AMPA density feeds back into receptor_conductance ceiling for next cycle --- **G expression**: ```Gen POSTSYNAPSE bAP_ctx ms -- Ca Influx CaNDMAEnterMax: ( active: 2x ) CaNDMAEnterMed: ( active: 4x ) NOT bAP_ctx: ms -- Ca Influx CaNDMAEnterMedNotBap: ( active: 4x ) CaNDMAEnterLow: ( active: 12x ) -- Ca Clearence CaClearance: ( active: 24x ) # Low -- V Influx VPostMax: accumulator VPostMed: accumulator VPostLow: accumulator -- V Clearence VPostClearance: accumulator POST-AMPA NOT bAP_ctx ms -- Na Influx NaAMPAEnterMax: ( active: 2x ) NaAMPAEnterMed: ( active: 4x ) POST-NA-CLEAR NOT bAP_ctx ms -- Na Clearence NaClearanceHigh: accumulator NaClearanceLow: accumulator TUN-POST-AMPA TunPossible_ctx sec CheckTunPostAmpa: ( active: 60x ) TryTunUpPostAmpa_ctx sec PossibleUpPostAmpaTun: ( active: 10x ) TryTunDownPostAmpa_ctx sec PossibleDownPostAmpaTun: ( active: 10x ) ``` **Tubs:** - **Na**: Ioni entranti tramite AMPA receptors - **NT**: - **Ca2+**: Ioni entranti tramite NMDA - **VPost**: il voltage che viene sentito in DB - **eCB**: - **Nox**:? --- ```Gen POSTSYNAPSE type: container expansion: - POST-AMPA ( full: 10x, active: 5x, empty: 2x ) # modulated_by: TUN-POST-IC # possible/actual - POST-NA-CLEAR ( full: 1x, active: 1x, empty: 0x ) # modulated_by: ?? tub_local: - Ca2+ ( full: 60x, active: 30x, empty: 0x ) - Na ( full: 60x, active: 30x, empty: 0x ) - Nox ( full: 100x, active: 20x, empty: 0x ) # Nitric Oxide (NO): A gas that diffuses freely. - eCB ( full: 100x, active: 20x, empty: 0x ) # Endocannabinoids (e.g., 2-AG) tub_intricated: - NT ( contained_by: SYNAPSE ) - VPost ( contained_by: BD ) context_intricated: - bAp_ctx ( contained_by: SOMA ) ``` ### ms: behaviors POST ![post-ltp-ltd.png](.attachments/post-ltp-ltd.png) ##### CaNDMAEnterMax: accumulator ```Gen CaNDMAEnterMax: ( active: 2x ) type: accumulator contained_by: POSTSYNAPSE in_context: bAp_ctx hypothesis: NOT (Ca2+ full) AND (Na fullness OR Na mediumness) action: [Ca2+ increase] trace: ``` ##### CaNDMAEnterMed: accumulator ```Gen CaNDMAEnterMed: ( active: 4x ) type: accumulator contained_by: POSTSYNAPSE in_context: bAp_ctx hypothesis: NOT (Ca2+ full) AND (Na emptiness) action: [Ca2+ increase] trace: ``` ##### CaNDMAEnterMedNotBap: accumulator ```Gen CaNDMAEnterMedNotBap: ( active: 4x ) type: accumulator contained_by: POSTSYNAPSE in_context: NOT bAP_ctx hypothesis: NOT (Ca2+ full) AND (Na fullness) action: [Ca2+ increase] trace: ``` ##### CaNDMAEnterLow: accumulator ```Gen CaNDMAEnterLow: ( active: 12x ) type: accumulator contained_by: POSTSYNAPSE in_context: NOT bAP_ctx hypothesis: NOT (Ca2+ full) AND (Na mediumness) action: [Ca2+ increase] trace: ``` #### CaClearance: accumulator ```Gen CaClearance: ( active: 24x ) # Low type: accumulator contained_by: POSTSYNAPSE in_context: NOT bAP_ctx hypothesis: NOT (Ca2+ empty) action: [Ca2+ decrease] trace: None ``` ##### VPostMax: accumulator ##### VPostMed: accumulator ##### VPostMin: accumulator ##### VPostClearance: accumulator Il clearance lo facciamo qui nel container dove creaiamo anche i VPost, perche' altrimenti, se lo facessimo in DB, perderemmo l'aspetto temporale della contribuzione dei singoli POST. ## POST-AMPA: Container ```Gen POST-AMPA type: container tub_intricated: - NT ( contained_by: SYNAPSE ) context_intricated: - Na ( contained_by: POSTSYNAPSE ) ``` ### ms: behaviors AMPA ##### NaAMPAEnterMax: accumulator ```Gen NaAMPAEnterMax: ( active: 2x ) type: accumulator contained_by: POST-AMPA in_context: NOT bAP_ctx hypothesis: (NT fullness) action: [Na increase] trace: ``` ##### NaAMPAEnterMed: accumulator ```Gen NaAMPAEnterMed: ( active: 4x ) type: accumulator contained_by: POST-AMPA in_context: NOT bAP_ctx hypothesis: (NT mediumness) action: [Na increase] trace: ``` ## POST-NA-CLEAR: Container Il clearance lo mettiamo qui come container, perche' gli AMPA creano, e questo container pompa fuori. Qui non e' un problema di perdere l'integrazione temporale, perche' gli AMPA sono tutti uguali nel loro behavior. Abbiamo messo gli AMPA come container perche' cosi' possiamo modularne la numerosita'. ```Gen POST-NA-CLEAR type: container context_intricated: - Na ( contained_by: POSTSYNAPSE ) ``` ### ms: behaviors NA-CLEAR #### NaClearanceHigh: Interacting #### NaClearanceLow: Interacting #### TUN-POST-AMPA: Tuner ```Gen TUN-POST-AMPA type: tuner contained_by: BEH-POST tunes: BEH-POST/expansion/BEH-POST-IC tub_modulation: # in TUN agiamo su POS/ACT - posMod ( fullness: None, active: BEH-POST-IC/fullness, empty: 0x) # riferimento a possible di BEH-PRE - actMod ( fullness: None, active: BEH-POST-IC/active, empty: BEH-POST-IC/emptiness) # riferimento a active di BEH-PRE context_intricated: - TunPossible ( contained_by: DAY-N ) tub_local: tub_intricated: ``` ##### CheckTunPostAmpa: contextor ```Gen CheckTunPostAmpa: ( active: 60x ) type: contextor contained_by: TUN-POST-AMPA in_context: TunPossible_ctx condition: tbd1 out_context: TryTunUpPostAmpa_ctx condition: tbd2 out_context: TryTunDownPostAmpa_ctx ``` ##### PossibleUpPostAmpaTun: accumulator ```Gen PossibleUpPostAmpaTun: ( active: 10x ) type: accumulator contained_by: TUN-POST-AMPA in_context: TryTunUpPostAmpa_ctx hypothesis: action: trace: ``` ##### PossibleDownPostAmpaTun: accumulator ```Gen PossibleDownPostAmpaTun: ( active: 10x ) type: accumulator contained_by: TUN-POST-AMPA in_context: TryTunDownPostAmpa_ctx hypothesis: action: trace: ```