# Equations for capump.mod

    INITIAL {
        ica = 0
        ica_pmp = 0
        ica_pmp_last = 0
        SOLVE pmp STEADYSTATE sparse
    }

    BREAKPOINT {
        SOLVE pmp METHOD sparse
        ica_pmp_last = ica_pmp
        ica = ica_pmp
    }

    KINETIC pmp {
        ~ cabulk <-> cam (width/tau, width/tau)
        ~ cam + pump <-> capump ((1e7)*k1, (1e10)*k2)
        ~ capump <-> cao + pump ((1e10)*k3, (1e10)*k4)
        ica_pmp = (1e-7)*2*FARADAY*(f_flux - b_flux)

        : ica_pmp_last vs ica_pmp needed because
        : of STEADYSTATE calculation
        ~ cam << (-(ica - ica_pmp_last)/(2*FARADAY)*(1e7))

        CONSERVE pump + capump = (1e13)*pump0
        COMPARTMENT width {cam}    : volume has dimensions of um
        COMPARTMENT (1e13) {pump capump} : area is dimensionless
        COMPARTMENT 1(um) {cabulk}
        COMPARTMENT (1e3)*1(um) {cao}

        cai = (0.001)*cam
    }