Effect of macrophage suppression with silica on the proliferation of Schwann cells during Wallerian degeneration.
Effects of macrophage suppression on Schwann cell proliferation in Wallerian degeneration was investigated in vitro with thymidine autoradiography. Sciatic nerves of C57BL mice were transected shortly after an intraperitoneal injection of silica dust and Schwann cells were harvested at 1, 2, 3, 5, 7, and 10 days post-transection. In silica treated mice, Schwann cells from post-transected nerve stumps proliferated despite marked suppression of macrophages, although there was some initial delay. The results of this study suggest that the mechanism of Schwann cell proliferation is multifactorial and in addition to the influence of growth factors mediated and released by macrophages, other factor(s) such as degenerated axolemma may play a more pivotal role in Schwann cell proliferation in vivo.
Kubota
A
A
Department of Neurology, Yokohama City University School of Medicine, Japan.
Komiyama
A
A
Matsumoto
M
M
Suzuki
K
K
D000818:Animals; D002452:Cell Count / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003714:Denervation; D005260:Female; D007274:Injections, Intraperitoneal; D008264:Macrophages / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D008854:Microscopy, Electron; D012583:Schwann Cells / Q000473:pathology*; D012584:Sciatic Nerve / Q000473:pathology; D012822:Silicon Dioxide / Q000494:pharmacology*; D013997:Time Factors; D014855:Wallerian Degeneration / Q000473:pathology*
D012822:Silicon Dioxide