Teratogenic effects of pantothenic acid antagonists on animal embryos.

Abstract

1. When ω-methyl pantothenic acid (PaA) was injected into yolk sac before incubation, 5mg dose affected only slightly the chicken development, but 10mg dose caused the death of embryos in 70per cent. Addition of PaA seemed to improve the inhibitory effect of ω-methyl PaA in antagonistic way.2. Bis (N-methyl pantoyl-β-aminoethyl) disulfide (MPAED) also has an inhibitory effect on the development of embryo, and it was more effective than ω-methyl PaA. The inhibitory action was not improved by PaA but prevented by pantethine. MPAED was regarded as an antimetabolite of pantetheine level.3. The anomalies observed macroscopically in these experiments included abnormalities of the brain, eye and beak in a high rate. These facts demonstrate the necessity of PaA for the early embryonic development of the chick, i.e. the differentiation of nervous system and the formation of skeleton system. It is interesting that the injection of ω-methyl PaA on the fourth day of incubation caused no remarkable effects.4. When PaA deficiency was instituted by ω-methyl PaA before breeding in mice, the conceiving ratio was considerably decreased and the fetal death with resorption occurred in many cases. Only two embryos survived, but anomalies, i.e. exencephalocele and hemorrhage, were observed in them.