title: Fetal membrane dynamics.
abstract: The validity of the concepts of exchange and net flow and of the method used to measure them was proved by utilizing a standard artificial membrane. The exchange rates across the amniochorion of D- and L-isomers of various amino acids have been measured. They do not differ. Rates of exchange of water, glucose, and mannitol across the umbilical cord were determined and were noted to be considerably slower than the rates for these substances across the amniochorion.
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000650:Amnion / Q000378:metabolism; D000653:Amniotic Fluid / Q000378:metabolism; D005321:Extraembryonic Membranes / Q000378:metabolism*; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008353:Mannitol / Q000378:metabolism; D008431:Maternal-Fetal Exchange; D008715:Methionine / Q000378:metabolism; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D014470:Umbilical Cord / Q000378:metabolism; D014867:Water / Q000378:metabolism
chemical_list: D000596:Amino Acids; D014867:Water; D008353:Mannitol; D008715:Methionine; D005947:Glucose