Dendritic topography of neurons of the retroambiguus nucleus in cat.

In 18 cats of different ages the topography of dendrites of the retroambiguus nucleus was established with Golgi impregnation method. The large and medium neurons of the nucleus send their longest dendrites mainly into dorsomedial and ventrolateral directions. The former dendrites enter the nervous tract area such as pyramidal, medial vestibulo-bulbo-spinal, ponto-bulbo-spinal and tecto-bulbo-spinal. The ventrolaterally directed dendrites reach the area in which pass lateral vestibulo-bulbo-spinal tract and fibers of the lateral reticular system. The dendrites always project outside of the center (nucleus). Thus, the term center should comprise not only perikaryons but also the area of dendritic tree which receives most of the afferent fibers. It is suggested to introduce two terms, viz., the "input area" which is formed by dendritic tree of the neurons belonging to the nucleus in the section and the "input space" as the dendritic tree considered in the three dimensions.