Levels of myo-inositol in normal and degenerating peripheral nerve.

Abstract

Abstract—Free inositol was measured in peripheral nerves of the monkey, rabbit, rat, frog and lobster; levels in mammalian nerve were similar, and two to three times greater than in the other species. Concentrations of myo‐inositol in rabbit tibial nerve increased from proximal to distal segments; in optic nerve the concentrations decreased with greater distance from the retina. In the early stages of Wallerian degeneration rabbit tibial nerve contained 25 per cent less free myo‐inositol, rat nerve 50 per cent less. Rabbit nerves were analysed at 2 and 5 weeks after section; by 5 weeks levels of myo‐inositol had increased to 50 per cent above normal. Similar changes were found in degenerating rabbit optic nerve. The combination of galactose feeding and nerve section resulted in reduction of the myo‐inositol in rat sciatic nerve to one‐fifth of the control value; galactitol in the nerve decreased by 50 per cent after section. The evidence suggests that myo‐inositol in nerve is located mainly in Schwann cells or glia.