the effect ( s ) of divalent cations in supporting the alpha-latrotoxin-induced release response seem ( s ) to occur primarily at step ( s ) beyond toxin binding because ( a ) the stimulatory effects of the various cations on release were not matched by parallel effects on binding , and ( b ) ca2+ maintained its ability to stimulate fast release even when toxin binding had occurred in a ca2+-free medium .
C0007448
divalent cations
C0007447
cations