Nonpermissive nature of fish optic nerves to axonal growth is due to presence of myelin-associated growth inhibitors.
Fish optic nerve sections were recently shown to be nonpermissive to growth of adult retinal axons. In addition, fish optic nerve myelin was found to inhibit growth of adult retinal axons and this inhibition was neutralized by IN-1 antibodies (known to block rat myelin-associated inhibitors). In this study we examined whether the growth nonpermissiveness of fish optic nerves which had not been injured prior to their excision results, at least in part, from the presence of myelin-associated growth inhibitors. It was found that preincubation of the sections with IN-1 antibodies, known to recognize and neutralize the myelin-associated growth inhibitors of the rat central nervous system, increases sixfold the number of axons that grow on these sections. This demonstrates that fish myelin-associated growth inhibitors, which are similar to those of rat, are at least partly responsible for the growth nonpermissiveness of normal fish optic nerves.
Sivron
T
T
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Schwartz
M
M
D000818:Animals; D001369:Axons / Q000502:physiology*; D006054:Goldfish / Q000502:physiology*; D006131:Growth Inhibitors / Q000378:metabolism*; D009186:Myelin Sheath / Q000378:metabolism*; D016501:Neurites / Q000502:physiology; D009900:Optic Nerve / Q000502:physiology*
D006131:Growth Inhibitors