title: Enzyme analysis of mouse extra-embryonic tissues.
abstract: We have separated for enzyme analysis the following layers that surround the conceptus at midgestation: decidua, trophoblast, parietal endoderm (including Reichert's membrane), visceral endoderm, yolk-sac mesoderm and amnion. Measurement of several catabolic enzyme activities (N-acetyl-beta, D-hexosaminidase, beta-glucuronidase, alkaline and acid phosphatases and non-specific esterases) in these tissues indicates that they are biochemically distinct, perhaps reflecting the different functions that they perform in providing the embryo proper with a desirable environment for differentiation and development. Our studies also provide an example of how visceral endoderm cells can effectively block passage of maternal macromolecules (in this case a serum esterase) in the fetal circulation. Finally, since there is often difficulty in distinguishing among early embryonic and extra-embryonic cell types produced in teratocarcinoma cultures, we have considered how our observations might be of use in the respect, particularly in discriminating between visceral and parietal endoderm.
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000650:Amnion / Q000201:enzymology; D000818:Animals; D003656:Decidua / Q000201:enzymology; D004591:Electrophoresis, Polyacrylamide Gel; D004622:Embryo, Mammalian / Q000201:enzymology*; D004707:Endoderm / Q000201:enzymology; D004950:Esterases / Q000378:metabolism; D005260:Female; D005966:Glucuronidase / Q000378:metabolism; D006596:Hexosaminidases / Q000378:metabolism; D008648:Mesoderm / Q000201:enzymology; D051379:Mice; D014327:Trophoblasts / Q000201:enzymology
chemical_list: D004950:Esterases; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D006596:Hexosaminidases; D005966:Glucuronidase