title: Early synaptogenesis in the spinal cord of human embryos.
abstract: Synaptogenesis in the spinal cord was studied by electron microscopy in human embryos ranging from four to six weeks of intrauterine life. The first synapses were found in the motor nucleus of 6-mm human embryos. A hypothesis is suggested about the role of these early synapses in neuronal development.
mesh_terms: D002454:Cell Differentiation; D002465:Cell Movement; D005865:Gestational Age; D006801:Humans; D008854:Microscopy, Electron; D009046:Motor Neurons / Q000166:cytology; D013116:Spinal Cord / Q000196:embryology*; D013569:Synapses / Q000648:ultrastructure*