title: Studies of Schwann cell proliferation. I. An analysis in tissue culture of proliferation during development, Wallerian degeneration, and direct injury.
abstract: In this paper the stimuli for and pattern of Schwann cell proliferation are defined under various experimental conditions. We used a tissue culture system in which fetal rat dorsal root ganglia, treated to eliminate contaminating fibroblasts (Wood, P., 1976, Brain Res. 115:361--375), appear to recapitulate many aspects of the developing peripheral nervous system. We observed that: (a) proliferation of Schwann cells on neurites is initially rapid, but, as each neurite becomes fully ensheathed, division slows considerably and is confined to the periphery of the outgrowth; (b) during the period of rapid proliferation, excision of the ganglion causes a rapid decay in the number of dividing cells; (c) excision of the ganglion from more established cultures in which there was little ongoing proliferation resulted in a small increase in labeling at the site of excision for all Schwann cells and a substantial increase in labeling for myelin-related cells with a peak labeling period at 4 d; (d) direct mechanical injury during Wallerian degeneration is mitogenic for Schwann cells; (e) a variety of potential mitogens failed to stimulate Schwann cell proliferation, and (f) replated cells have a slightly higher level of proliferation and show a small and variable response to the addition of cAMP.
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology*; D003994:Bucladesine / Q000494:pharmacology; D002455:Cell Division; D002772:Cholera Toxin / Q000494:pharmacology; D046508:Culture Techniques; D005727:Ganglia, Spinal / Q000166:cytology / Q000502:physiology; D008934:Mitogens / Q000494:pharmacology; D009186:Myelin Sheath; D009410:Nerve Degeneration; D051381:Rats; D012583:Schwann Cells / Q000166:cytology*; D013997:Time Factors; D014855:Wallerian Degeneration
chemical_list: D008934:Mitogens; D003994:Bucladesine; D002772:Cholera Toxin