Premium
Cytochemical Maturation of the Notochord in Dysraphic Mice
Author(s) -
WILSON DORIS B.,
WYATT DARLENE P.
Publication year - 1990
Publication title -
congenital anomalies
Language(s) - English
Resource type - Journals
eISSN - 1741-4520
pISSN - 0914-3505
DOI - 10.1111/j.1741-4520.1990.tb00184.x
Subject(s) - notochord , ultrastructure , embryo , neural tube , biology , ruthenium red , neural fold , cytochemistry , mesenchymal stem cell , anatomy , glycogen , microbiology and biotechnology , embryogenesis , pathology , chemistry , biochemistry , neural plate , organic chemistry , calcium , medicine
Functional aspects of notochordal maturation in dysraphic loop‐tail ( Lp ) mice were analyzed by means of ultrastructural cytochemistry on embryos at 9–12 days of gestation. Notochordal cells in normal (+/+; Lp /+) and dysraphic abnormal ( Lp/Lp ) embryos showed ultrastructural features consistent with secretory activity, particularly at 10 and 11 days. With specific cytochemical staining, glycogen was observed as thiocarbohydrazide‐silver proteinate particles sparsely scattered throughout notochordal cells of normal and abnormal embryos at 9 and 10 days, with aggregates common at 11 and 12 days. With tannic acid and ruthenium red treatment, the perinotochordal space in abnormals showed differences in the density of stained filaments from that in normal embryos, suggesting a defect in glycosaminoglycan deposition. In abnormal embryos, the notochord became located relatively more distant from the open neural folds than from the closed neural tube in normal littermates, and the arrangement of the adjacent mesenchymal cells was irregular and less dense than that in the normal embryos. Thus, although the ultrastructure of the notochordal cells was relatively normal, the features indicative of aberrant interactions among the notochord, neural folds, and adjacent mesenchymal cells may be of significance in the etiology of dysraphism in this mutant.