/******************************************************/
/* A simple model of a single AZ at the calyx of Held */
/*                                                    */
/* Definition of AMPARs                               */
/*                                                    */
/* Matthias Hennig                                    */
/* mhennig@inf.ed.ac.uk                               */
/*						      */
/* Modified by D. Kufel on 03/01/2018. Implemented 
kinetic scheme 2 from the paper.		      */ 
/******************************************************/
/* source: https://senselab.med.yale.edu/ModelDB/showmodel.cshtml?model=85981 */

/* the transmitter in question */
DEFINE_LIGAND Glu {
  DIFFUSION_CONSTANT = D
}

/* AMPA receptor kinetics */
DEFINE_REACTION AMPAR {
  C0[>C1{Rb:+Glu,POSITIVE_POLE}]
  C1[>C2{Rb:+Glu,POSITIVE_POLE}][>O1{Ro1}]  [>C0{Ru1:-Glu,POSITIVE_POLE}][>D1{Rd0}]
  C2[>C3{Rb:+Glu,POSITIVE_POLE}][>O2{Ro1}][>C1{Ru1:-Glu,POSITIVE_POLE}][>D2{Rd1}]
  C3[>C4{Rb:+Glu,POSITIVE_POLE}][>O3{Ro1}][>C2{Ru1:-Glu,POSITIVE_POLE}][>D3{Rd1}]
  C4                                     [>O4{Ro1}][>C3{  Ru1:-Glu,POSITIVE_POLE}][>D4{Rd1}]

  O1[>C0{Rc1}]
  O2[>C1{Rc1}]
  O3[>C2{Rc1}]
  O4[>C3{Rc1}]

  D1[>C0{Rr1}]
  D2[>C1{Rr1}]
  D3[>C2{Rr1}]
  D4[>C3{Rr1}]

  REFERENCE_STATE C0 {
    Glu
    NUMBER_BOUND = 0
  }
}