the effects of intraventricularly ( i.c.v . ) administered divalent cations , cation chelators and an ionophore ( a23187 ) on antinociception produced by i.c.v . administration of morphine or dibutyryl guanosine 3':5'-cyclic monophosphate ( db c-gmp ) were quantitated in the mouse tail-flick procedure .
C0007448
divalent cations
C0007447
cation