Your browser doesn't support javascript.
loading
Developmental changes in spinal motoneuron dendrites in neonatal mice.
Li, Yan; Brewer, Diana; Burke, Robert E; Ascoli, Giorgio A.
Afiliação
  • Li Y; Laboratory of Neural Control, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, USA.
J Comp Neurol ; 483(3): 304-17, 2005 Mar 14.
Article em En | MEDLINE | ID: mdl-15682391
We examined the age-dependent morphological changes of lumbar spinal motoneurons (MNs) in neonatal Swiss-Webster mice during the first 2 weeks of postnatal life. Neurons labeled by intracellular injection of biocytin in hemisected lumbosacral spinal cords in vitro were reconstructed from serial sections. Digitized data were compared for young (P3; postnatal days 2-4; n = 9) and older animals (P11; postnatal days 10-13; n = 8). As expected, measures of dendritic size (e.g., stem branch diameter, total surface area, maximum distance to tips, and lateral tree spread) were all significantly greater for P11 than for P3 mice. In contrast, the number of dendrites per MN and parameters related to tree topology (e.g., terminations per tree and maximum branch order), although slightly greater for P11 animals, were not significantly different between the two ages. Dendrite growth appeared to be proportional throughout the tree because the ratios between average terminal and internal branch lengths were similar for the two groups. Furthermore, this elongation was proportional to enlargement of overall spinal cord dimensions. A variety of other morphometric measures showed no significant difference between age groups. The relative constancy of MN dendritic topology up to P13 was surprising, given the striking maturation in motor function during this time period.
Assuntos
Buscar no Google
Base de dados: MEDLINE Assunto principal: Medula Espinal / Dendritos / Lisina / Neurônios Motores Idioma: En Ano de publicação: 2005 Tipo de documento: Article
Buscar no Google
Base de dados: MEDLINE Assunto principal: Medula Espinal / Dendritos / Lisina / Neurônios Motores Idioma: En Ano de publicação: 2005 Tipo de documento: Article