Fig. 11. Repression of caspase-3 expression in the caspase-3-morpholino antisense oligonucleotide (MO)-injected embryos. The active form of caspase-3 was detected by immunohistochemistry with anti-active caspase-3 antibody. (A) control, embryos injected with MO (1 ng) at 9 h.p.f. (B) caspMO, embryos injected with caspase-3-MO (1 ng) at 9 h.p.f. (C) Caspase-3 activity against Ac-DEVD-MCA was compared between the control MO-injected and caspase-3-MO-injected embryos at 9 h.p.f. Each value indicates the mean ± s.d. of three independent experiments. An asterisk denotes a statistically significant difference between the control MO-injected and the caspase-MO-injected embryos (P<0.05, Student's t-test). The activity of the caspase-3-MO-injected embryos was significantly lower than that of the controls.