The lipids of human sciatic nerve by age group.

Lipid analysis of normal human peripheral (sciatic) nerve in 18 cases revealed suggestive evidence of quantitative changes in phospholipids and glycolipids at the extremes of life. Total phospholipids were highest in the newborn and lowest over 65 years of age, while glycolipids were lowest in the neonatal period. Cholesterol did not vary with age. Analysis of the major phospholipid components showed their percentage distribution to be age stable, and phosphatidyl serine to be enriched at all ages. The biochemical findings indicate loss of axonal-myelin constituents after 65 years of age. They correlate with histological and physiological studies on peripheral nerve and with the role of the acidic phospholipids as membrane cation-transporters.