Distribution of the growth associated protein GAP-43 in the central processes of axotomized primary afferents in the adult rat spinal cord; presence of growth cone-like structures.
GAP-43-immunolabelled structures were visualized by electron microscopy in the adult rat L4-L5 superficial dorsal horn 2 weeks after sciatic nerve transection. The majority of immunolabelled elements were unmyelinated axons, but some synaptic terminals and myelinated axons also labelled. The labelled unmyelinated axons were commonly located in prominent bundles which on serial section analysis could be followed into larger single trunks. These enlargements contain many organelles and give rise to smaller processes, which is compatible with their being growth cones. Sciatic nerve transection may result, therefore, in central regenerative processes which reorganize the neuropil and contribute to the decreased sensibility and pain that follows peripheral nerve section.
Coggeshall
R E
RE
Department of Anatomy and Neuroscience, University of Texas Medical Branch, Galveston 77550.
Reynolds
M L
ML
Woolf
C J
CJ
D000344:Afferent Pathways / Q000502:physiology*; D000818:Animals; D001369:Axons / Q000502:physiology* / Q000648:ultrastructure; D003712:Dendrites / Q000502:physiology / Q000648:ultrastructure; D003714:Denervation; D019922:GAP-43 Protein; D006133:Growth Substances / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000032:analysis / Q000378:metabolism*; D016253:Microscopy, Immunoelectron; D008959:Models, Neurological; D009413:Nerve Fibers, Myelinated / Q000502:physiology / Q000648:ultrastructure; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000378:metabolism*; D051381:Rats; D012584:Sciatic Nerve / Q000502:physiology*; D013116:Spinal Cord / Q000502:physiology* / Q000648:ultrastructure; D013569:Synapses / Q000502:physiology / Q000648:ultrastructure
D019922:GAP-43 Protein; D006133:Growth Substances; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins