A study on the immunocytochemical localization of neurofascin in rat sciatic nerve

We examined the localization of neurofascin (NF) in the sciatic nerve of rat. In the myelinated fibers, neurofascin localizes strongly in the nodal axolemma except the small central cleft and also expresses in the paranodes, and weakly in the Schmidt-Lanterman incisures. In the paranodes, NF localizes around the axolemma and it expresses in the apposing membrane of paranodal loops. Axoplasm, compact myelin and cytoplasm of Schwann cell do not express NF at all. In the Schmidt-Lanterman incisures, NF is expressed weakly along the Schwann cell membrane. We propose that neurofascin may be a plasmalemmal integral protein of Schwann cell in the paranode and plays some important roles for the maintenance of axo-glial junctions at the paranode. It may also have some roles for maintaining the structure of Schmidt-Lanterman incisure and have some relations with proteins localizing in the node.

Nerve glucose, fructose, sorbitol and myo-inositol in experimental diabetes

In a trial to investigate the biochemical changes associated with diabetic polyneuropathy, nerve contents of glucose, fructose, sorbitol and myoinositol were studied in 20 normal healthy rats versus 20 rats with alloxan-induced diabetes. There was significant increase in the nerve contents of glucose, fructose and sorbitol of diabetic animals as compared to controls. On the contrary, nerve myoinositol showed significant decline in diabetic rats. It appears that the accumulation of alcohol sugars leads to tissue swelling, thickening of basement membranes and reduction in the nerve conduction velocity of the affected diabetic nerves. Moreover, the decreased nerve myoinositol found in diabetic animals, could be an integral factor in the pathogenesis of diabetic neuropathy, since decreased nerve myoinositol inhibits series of biochemical events responsible for maintaining nerve excitability and conductivity