title: [Structure of motor nuclei of the rat spinal cord during postnatal ontogeny (according to the results of light and electron microscopic studies].
abstract: Ultrastructural peculiarities of motoneurons and synapses in the area of the motor nuclei in the spinal cord of 10--18-day-old rats were revealed electron microscopically. It was stated that by the 14th day of age motoneurons acquire features of mature neurons. Several types of synapses were found: axo-dendritic, axo-somatic, axo-axonal. Axo-dentritic synapses prevail in neuropil of the spinal cord motor nuclei at the age studied. Synapses in 10--13-day-old rats sometimes demonstrate an immature ultrastructure. A peculiar feature of the neuropil is the presence of dendritic bundles consisting of dendrites various in their calibers or of dendrites and preterminal parts of axons. The data obtained from the spinal cord of rats at the age up to 1 month neurohistologically treated add something new to our knowledge on structure of motor nuclei of the rat spinal cord in postnatal ontogenesis.
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000648:ultrastructure; D001369:Axons / Q000648:ultrastructure; D002462:Cell Membrane / Q000648:ultrastructure; D003712:Dendrites / Q000648:ultrastructure; D008854:Microscopy, Electron; D008870:Microtubules / Q000648:ultrastructure; D009046:Motor Neurons / Q000648:ultrastructure; D009836:Oligodendroglia / Q000648:ultrastructure; D051381:Rats; D013116:Spinal Cord / Q000648:ultrastructure*; D013569:Synapses / Q000648:ultrastructure; D013572:Synaptic Vesicles / Q000648:ultrastructure
vernacular_title: O strukture motornykh iader spinnogo mozga krysy v postnatal'nom ontogeneze (po dannym sveto-opticheskogo i élektronno-mikroskopicheskogo issledovaniia).