Laminin-immunoreactive glia distinguish regenerative adult CNS systems from non-regenerative ones.
AUTOR(ES)
Liesi, P
RESUMO
Most regions of the adult mammalian central nervous system (CNS) do not support axonal growth and regeneration. Laminin, expressed by cultured astrocytes and known to promote neurite outgrowth of cultured neurons, is normally present in brain basement membranes, and only transiently induced in adult brain astrocytes by injury. Here I provide three lines of evidence which suggest that the continued expression of laminin by astrocytes may be a prerequisite for axonal growth and regeneration in adult CNS. Firstly, laminin is continuously present in astrocytes of adult rat olfactory bulb apparently in close association with the olfactory nerve axons. Secondly, laminin is continuously expressed by astrocytes in adult frog brain, and sectioning of the optic tract further increases laminin immunoreactivity in astrocytes of the optic tectum during the period of axonal regeneration. Lastly, laminin appears normally in astrocytes of the frog and goldfish optic nerves which regenerate, but not in astrocytes of the rat or chick optic nerves which do not regenerate. The selective association of laminin with axons that undergo growth and regeneration in vivo is consistent with the possibility that astrocytic laminin provides these central nervous systems with their regenerative potential.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=554536Documentos Relacionados
- Regenerative and non-regenerative calcium transients in hamster eggs triggered by inositol 1,4,5-trisphosphate.
- Fucoid Zygotes Germinate from Their Darkest Regions, Not Their Brightest Ones.
- Beware! Preimplantation genetic diagnosis may solve some old problems but it also raises new ones.
- Do neurons in the vertebrate CNS migrate on laminin?
- Natural covalent complexes of nucleic acids and proteins: some comments on practice and theoryon the path from well-known complexes to new ones.