title: Cell contacts between chorda-mesoderm and the overlaying neuroectoderm (presumptive central nervous system) during the period of primary embryonic induction in amphibians.
abstract: Using transmission and scanning electron microscopy we were able to show that during primary embryonic induction in amphibians (Triturus alpestris) the interspace between the inducing chorda-mesoderm and the reacting ectoderm (presumptive medullary plate) of mid-gastrula stages is traversed by cell projections starting from cells of both tissue layers. In addition intimate membrane contacts between the main bodies of the ectodermal and chorda-mesodermal cells could be observed. It could be ruled out that cytoplasmic bridges (anastomosis) exist between cells of inducing chorda-mesoderm and reacting ectoderm, which would allow a free transfer of inducing substances without passing through membranes, as Eakin and Lehmann [1] have postulated. The possible role of cell to cell contact for neural induction is emphasized.
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002450:Cell Communication; D004475:Ectoderm / Q000166:cytology*; D004627:Embryonic Induction; D008648:Mesoderm / Q000166:cytology*; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D009420:Nervous System / Q000196:embryology; D012455:Salamandridae / Q000196:embryology*; D014562:Caudata / Q000196:embryology*