title: Immunohistochemical study of carbonic anhydrase III in the extraocular muscles of human embryos.
abstract: The differentiation of extraocular muscles was studied immunohistochemically in externally normal human embryos (Carnegie stages 13-23), using antibodies to carbonic anhydrase (CA) III and beta-enolase as the markers of type 1 and type 2 muscle fibers, respectively. At stage 18, some myoblasts were immunoreactive to beta-enolase antibodies, however, CA-III immunoreactivity was not observed around the optic vesicle. At stage 20, CA-III immunoreactivity appeared in some muscle fibers of extraocular muscles. From stage 21 to stage 23, CA-III-immunoreactive fibers increased and almost equalled the number of beta-enolase-immunoreactive fibers. These findings suggest that CA-III-immunoreactive type 1 fibers appear in the late stage of myogenesis compared with beta-enolase-immunoreactive type 2 fibers.
authors.affiliation: Department of Ophthalmology, Shimane Medical University, Izumo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Oguni
authors.forename: T
authors.initials: T
authors.lastname: Setogawa
authors.forename: O
authors.initials: O
authors.lastname: Tanaka
authors.forename: H
authors.initials: H
authors.lastname: Shinohara
authors.forename: K
authors.initials: K
authors.lastname: Kato
mesh_terms: D002256:Carbonic Anhydrases / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D009801:Oculomotor Muscles / Q000196:embryology* / Q000201:enzymology; D010751:Phosphopyruvate Hydratase / Q000032:analysis*
chemical_list: D002256:Carbonic Anhydrases; D010751:Phosphopyruvate Hydratase