ELECTRON MICROSCOPIC OBSERVATIONS ON THE EFFECT OF TRICHOSANTHIN TO BLASTOCYST

Rabbit blastocysts were treated in vitro with trichosanthin (2.5μg/ml)for 24 hours.Their ultrastructuralchanges were compared with those ofblastocysts of corresponding age eithercollected directly from the uteri ofpregnant rabbits or after culture invitro for 24 hours.It was found thatthe cells of inner cell mass were moreseverely injured than the trophoblastcells.While the trophoblast cells suf-fered only slight effects,degenerativechanges had already appeared in thecells of inner cell mass.The differencein the susceptibility of these two typesof cells to trichosanthin was discussed.