Table 1. Effects of various inhibitors on the first cleavage of mouse zygotes.

stage	1-cell	2-cell	dead	total
AM	1	44	1	46
vehicle	2	29	0	31
CH	48	25	12	85
vehicle	16	66	2	84
CP	14	135	1	150
vehicle	6	128	0	134

Late pronuclei stage zygotes (around E0.75) were cultured for 24 hours in presence of following inhibitors; AM: á-amanitin 100 µg/mL, CH: cycloheximide 10 µg/mL, CP: chloramphenicol 200 µg/mL, vehicle: 1% DMSO as vehicle control. Numbers of conceptuses reaching denoted cleavage stages were counted and presented. Numbers of independent trials: 5 for AM, 8 for CH and 14 for CP.