Die Massenverteilung in der markhaltigen Nervenfaser, bestimmt durch Röntgenabsorptionsmessung
On single nerve fibres of the frog (n. ischiadicus) absorption measurements with x-rays have been performed. The determinations give the following results: The myelinated fibre is to be considered as a rigid tube. The mass of the myelin sheath is about 0.3–0.4·10−12 g/µ3, and that of the axon only 1/5–1/8 of this value. The center of the myelin sheath contains about 50% lipids with one inner and one outer protein layer. No extractable lipids have been observed in the axon. The behaviour of the axon in the neighbourhood of the nodes of Ranvier has been studied after electrical stimulation. A complete description of the analytical technique and the results will soon be published.