Peripheral nerve energy metabolism in experimental diabetic neuropathy

Peripheral nerve has low energy demands at rest and when maximally stimulated. Coupled with the relatively high energy substrates available, it is more resistant to ischemia and anoxia than brain. Diabetic peripheral nerve, by virtue of its enhanced energy stores, and chronic hypoxia, has an increased resistance to ischemic conduction failure, and subsists proportionately more than tissues such as brain on anaerobic metabolism. Since anaerobic metabolism is very inefficient, however, a reduction in energy substrates can increase the risk of fiber degeneration. Glucose uptake into peripheral neural tissues (sciatic; L5 dorsal root ganglion; superior cervical ganglion) are markedly reduced. alpha-lipoic acid dose- dependently improves glucose uptake. This increase in glucose uptake increases energy stores without a reduction in nerve myoinositol.