text: On the other hand, high doses of okadaic acid (10 ng/mouse, i.c.v.) and << cantharidin >> (1 microg/mouse, i.c.v.), which also block [[ PP1 ]], and calyculin-A (0.1 fg/mouse-1 ng/mouse, i.c.v.), which inhibits equally both PP1 and PP2A, did not modify the morphine-induced antinociception.