Macrophage dependence of peripheral sensory nerve regeneration: possible involvement of nerve growth factor.
The levels of NGF and NGF receptor mRNA, the degree of macrophage recruitment, and the ability of sensory and motor axons to regenerate were measured in C57BL/Ola mice, in which Wallerian degeneration following a nerve lesion is very slow. Results were compared with those from C57BL/6J and BALB/c mice, in which degeneration is normal. We found that in C57BL/Ola mice, apart from the actual lesion site, recruitment of macrophages was much lower, levels of mRNA for both NGF and its receptor were raised only slightly above normal, and sensory axon regeneration was much impaired. Motor axons regenerated quite well. These results provide in vivo evidence that macrophage recruitment is an important component of NGF synthesis and of sensory (but not motor) axon maintenance and regrowth.
Brown
M C
MC
University Laboratory of Physiology, Oxford, England.
Perry
V H
VH
Lunn
E R
ER
Gordon
S
S
Heumann
R
R
D000818:Animals; D001369:Axons / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D008264:Macrophages / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008854:Microscopy, Electron; D009410:Nerve Degeneration / Q000187:drug effects / Q000502:physiology; D009414:Nerve Growth Factors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D009416:Nerve Regeneration / Q000187:drug effects / Q000502:physiology*; D009475:Neurons, Afferent / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D010525:Peripheral Nerves / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D017475:Receptors, Nerve Growth Factor; D012584:Sciatic Nerve / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure
D009414:Nerve Growth Factors; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D017475:Receptors, Nerve Growth Factor