X‐Ray Diffraction Studies on Peripheral Nerve Myelin

Hoglund G. and H. Ringertz. X‐ray diffraction studies on peripheral nerve myelin. The dimension of the radial repeating unit was measured on peripheral nerve from 15 species belonging to 4 vertebrate classes. In the fishes the dimension was 161 ± 3 Å and in the birds 182 ± 5 Å. In the mammalian and amphibian species the dimensions were in agreement with earlier work (185 ± 3 Å and 171 ± 3 Å, respectively). Diffraction patterns from brachial plexus nerves of sheep fetuses were obtained from a gestation age of approximately 90 days. Weak lines indicating a lower number of regularly arranged radial repeating units compared to older fetuses were obtained from fetuses between 90 and 105 days gestation age. The diffraction patterns from fetuses older than approximately 105 days gestation age were similar to those from peripheral nerves of adult sheep.