抄録
The appearance of two molecular markers of muscle differentiation, brain (BGP) and muscle-brain (MB-GP) type of glycogen phosphorylase, was studied immunohistochemically in the extraocular muscles of human embryos (Carnegie stages 13 to 23). During stages 13-18, there was no immunoreactivity to BGP and MB-GP antibodies around the optic vesicle. At stage 20, myogenic cells around the optic vesicle became immunoreactive to both BGP and MB-GP antibodies, however, the number of MB-GP immunoreactive cells was larger than that of BGP immunoreactive cells. At stage 21, MB-GP immunoreactive cells increased in number, but BGP immunoreactive cells decreased. At stage 23, BGP immunoreactivity disappeared from the extraocular muscles. These findings suggest that BGP appears transiently in a restricted population of extraocular muscles in the embryonic period and the isoenzyme pattern becomes adult type (MGP) in the late embryonic period.
