Topography of human placental receptors for epidermal growth factor.

摘要: Abstract These studies were undertaken to determine whether term human placental microvillus plasma membranes, which are exposed maternal blood, and basolateral in close proximity fetal blood capillaries, contain receptors for epidermal growth factor (EGF). two highly purified membranes bound 125I-EGF with similar affinity (apparent dissociation constants, 0.07-0.12 nM, but the total number of available was greater (8.2 pmol/mg protein) compared (4.9 membranes. Detailed characterization binding these revealed numerous similarities as well differences. The contained major (155 140 kDa) at least three minor (115, 175, 210 specific proteins. 115-kDa protein only found 155-kDa predominantly labeled microvillus, whereas 140-kDa addition protease inhibitors did not alter multiple proteins pattern EGF stimulated phosphorylation 140- both However, phosphorylated a extent equally Light electron microscope autoradiographic that preferentially associated data demonstrates presence outer cell syncytiotrophoblasts suggests may influence syncytiotrophoblast function by while also via