Evidence of a Proximo-Distal Movement along the Axon of Phospholipid synthesized in the Nerve-Cell Body

Abstract

PROXIMO-DISTAL movement along the axon of protein synthesized in the nerve-cell body has been investigated by the following method¹. A labelled precursor of protein (for example, ¹⁴C-amino-acid) is placed on the floor of the fourth ventricle and the protein is collected at the distal segment of the hypoglossal and vagus nerves. Under these experimental conditions an extensive synthesis of labelled protein occurs in the medulla oblongata, namely in the nerve-cell bodies of the hypoglossal, dorsal and ambiguus nuclei. On the other hand, the Schwann cells and the other components of the encephalic nerves incorporate a negligible amount of tagged amino-acid, its level into the blood being low.