Observations on the fine structure of the lateral vestibular nucleus (Deiters' nucleus) in the cat

Summary A study has been made of the ultrastructure of the lateral vestibular nucleus of the normal cat. The study includes light microscopical observations made in Golgi material. The internal structure of the various types of cells is described. The soma of the larger nerve cells is surrounded by a protoplasmic layer, constituted by astroglial sheets, dendrites and boutons; glial cell bodies are usually located outside the layer. The smaller nerve cells display few axosomatic synapses and may be in direct contact with myelinated fibres and glial perikarya. Spines are present on the soma of large and small nerve cells and on all parts of the dendrites. The proximal dendrites are usually the part of the neurons which is most amply supplied with boutons.Various types of boutons and cell junctions are described and an attempt is made to correlate the findings in electron micrographs with those made in Golgi sections.The study serves as a basis for observations made in experimental material where afferent fibres to the nucleus have been damaged.This investigation has been supported in part by Grant NB 02215-07 from the National Institute of Neurological Diseases and Blindness, US-Public Health Service. This aid is gratefully acknowledged.