## Abstract The properties of acid phosphatase from the cement gland of __Xenopus laevis__ embryos were investigated both biochemically and electrophoretically. The studies were made on excised glands at a preregressing stage (stage 35/36, Nieuwkoop and Faber staging series) and a regressing stage
Histological development of the cement gland in Xenopus laevis: A light microscopic study
β Scribed by Timothy A. Lyerla; John J. Pelizzari
- Publisher
- John Wiley and Sons
- Year
- 1973
- Tongue
- English
- Weight
- 712 KB
- Volume
- 141
- Category
- Article
- ISSN
- 0362-2525
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β¦ Synopsis
Abstract
The differentiation and degeneration of the cement gland in Xenopus laevis is described. The gland is first observed histologically at stage 19 (neural tube stage) as a packed group of apical ectoderm cells heavily laden with oocyte pigment granules, lying ventral to the cranial neural fold. By tailbud stage 35/36, the gland cells have increased in height and are approximately ten times taller than nonglandular apical ectoderm cells. The nuclei divide the gland cells into an apical region that is eosinophilic and contains oocyte pigment granules, and a basal region that contains clear droplets. The cells are decreasing in height by stage 40 (early tadpole) and begin to lose their pigment granules. Between stages 45 and 48, the pigment is extruded and the clear basal droplets diminish in number. From stage 48 to 49 the cells become vacuolated and the histotypic characteristics of the functional gland are lost. The gland is not vascularized, nor do phagocytic cells appear in its vicinity during any stage of its development. It remains bordered at its base by subjacent basal ectoderm during its entire life cycle of 10 to 12 days at room temperature.
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## Abstract The hydrolases Bβglucuronidase, Bβgalactosidase and NβacetylβBβDβglucosaminidase were examined in __Xenopus laevis__ for their pH optima, sedimentability by differential centrifugation and optimal incubation temperatures for their assays. Enzyme activities were enriched in the 20,000 Γ
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