preincubation with the divalent cation ionophore a23187 and calcium chelator ethyleneglycolbis ( beta-aminoethyl ether ) -n , n'-tetraacetic acid increases the efflux of both atp and adp ( to a lesser extent ) in these tumor mitochondria , indicating that the extraordinarily high concentrations of calcium form complexes with adenine nucleotides ( particularly atp ) and thus lower the effective concentrations of free nucleotides for translocation .
C0001459
adp
C0001413
adenine nucleotides