Types of neurons in nucleus olivaris inferior of the European bison.

The studies were carried out on the medullae oblongatae of four European bisons. Preparations made by means of the Golgi technique, as well as preparations stained by the Klüver-Barrera methods, were used. Two types of neurons were distinguished in nucleus olivaris inferior of the European bison. Type I (about 90% of neurons) are multipolar cells whose perikaryons measure from 25 to 40 microns. The multipolar cells generate 5-6 thick dendrites which next give off a number of branches. The dendritic tree is ball-shaped. A single long, thin axon arises from the surface of the perikaryon or branches from the initial segment of one of the dendrites. The axon adopts a course along the plane corresponding to the transverse section of brain stem. Type II (about 10% of neurons) are pear-shaped and rounded cells measuring from 25 to 30 microns. These cells generate 2-3 thick dendritic trunks which are concentrated at one pole of the perikaryon. The dendritic tree has a stream-like form. A single short and rather thin axon emerges from the surface of the perikaryon. Its course corresponds to the long axis of brain stem.