Neuroarchitectonics of the medulla oblongata of cattle

Abstract

The article presents data from the study of neuroarchitectonics of the medulla oblongata of cattle. The main attention was paid to the peculiarities of neuronal morphology, determination of their type and prevalence of a certain population of cells in the tissue. The study was performed on 23 brain samples taken from animals aged 2–11 years. To reveal the architectonics of neurons, methods of fabric impregnation with silver were used according to Golgi, Ramon-Kahal and Bolshovsky. The main criteria for determining the type of cells were such features as: cell body size, its shape, number and distribution of processes, their thickness, tortuosity and branching. According to the results, we can identify four main populations of neurons, which are represented by such morphofunctional cell types as: reticular, large polygonal (motor), small round (sensory) and spindle-shaped. The largest population consists of reticular neurons, the second most common are sensory, then motor and the least represented spindle-shaped. It was found that the population of sensory-type neurons includes such structures as the Gracilis and Cutaneus nucleus, the complex of olive inferior nuclei and the nucleus of the solitary tract. Motor are represented respectively in the dorsal, ventral and lateral motor nuclei, the hipoglossy nucleus, the ventral nucleus of the vagus nerve and the ventral subunit of the dorsal nucleus of the vagus nerve. Spindle-shaped neurons are represented only in the dorsal subunit of the dorsal nucleus of the vagus nerve, and reticular form the largest population represented by the reticular formation and the lateral nucleus. A certain pattern of distribution of cell types in the tissue is traced. Thus, the most archaic and architectural – reticular neurons form the center of cell mass, while specialized forms of cells – motor and sensory distributed on the periphery. In a separate type, spindle-shaped neurons of the dorsal nucleus of the vagus nerve are isolated, as cells of the transition link from reticular to motor.