Morphology of spinal ganglia of different segmentary levels in the domestic dog

Abstract

The spinal ganglia, which perform the function of the first link on the afferent impulses’ way from the receptors to the central nervous system, recognize internal and external irritations, and are the first to transform them into a nervous impulse. As the representatives of the peripheral nervous system, they are some of the main objects of the studies in contemporary neuromorphology. Based on the results of anatomic, neurohistological, histochemical, morphometric and statistical methods of the studies, we conducted a complex survey, revealing the morphology of spinal ganglia of different segmental levels in the domestic dog. In particular, we determined the differences in the microscopic structure and morphometric parameters of cervical, thoracic, lumbar and sacral spinal ganglia and the ganglia of the cervical and lumbar enlargements in mature domestic dogs. The study showed that the spinal ganglia of domestic dogs can have different skeletotopy, different shape and sizes due to their species peculiarity. Also, the surveyed animals, according to the results of our studies, had the cervical and thoracic spinal ganglia of oval, while the lumbar and sacral – spindle-like shapes. According to the results of morphometry, the area of the spinal ganglia in lengthwise section differed: the smallest area belonged to the thoracic, the largest to the sacral spinal ganglia. The density of neuronal arrangement per 0.1 mm2 of the area of the spinal ganglia correlated with their sizes: the highest parameter was identified for the thoracic spinal ganglia, the lowest – for the sacral. The conducted studies revealed that histo- and cyto-structure of the spinal ganglia is characteristic of notable differentiation of the nervous cells of small sizes. Therefore, we differentiated neurons of the spinal ganglia into large, medium and small. The highest quantity of large neurons was found in the sacral ganglia, and largest amount of medium-sized neurons – in the ganglia of the lumbar enlargement. In other ganglia, small neurons dominated. Correspondingly, different nuclear-cytoplasmic ratio in these neurons was determined, indicating different extent of morphofunctional condition of nervous cells. We determined content of localization and separation of nucleic acids in histostructure of the spinal cord at the tissue and cellular levels.

Evolutionary morphology of spinal nodes of poikilotherm vertebrate animals

“…Особливий інтерес у нейроморфології впродовж тривалого часу становлять спинномозкові вузли (Starchenko et al, 2018;Horalskyi et al, 2020), які є аферентними структурами рефлекторних дуг та основою первинних центрів на шляху передачі сенсорної інформації до центральної системи, забезпечуючи відповідні реакції на дію конкретних чинників (Medici & Shortland, 2015).…”

Morphological and morphometrical characteristics of cattle heart structure

“…Найменші морфометричні параметри (довжина, ширина кардіоміоцитів, об'єм кардіоміоцитів, об'єм їх ядер) були у кардіоміоцитах передсердь, в яких ЯЦВ було найбільшим і дорівнювало відповідно 0,0234 ± 0,0058 (табл. 1), що свідчило про менше морфофункціональне навантаження кардіоміоцитів передсердь порівняно з кардіоміоцитами шлуночків, адже найбільш морфофункціонально активними та зрілими соматичними клітинами є ті, для яких характерний низький індекс ЯЦВ і, навпаки, клітини з високим ЯЦМ є менш функціонально активними (Horalskyi et al, 2020).…”

Specific features of the morphology of the spinal nodes of homeothermal vertebrate animals in the comparative and anatomical series

“…Such reactions are controlled by the lower, oldest parts of the nervous system (Popele & Bosco, 2003). In vertebrates, such a department is the spinal cord with spinal nodes (Horalskyi et al, 2020;Sokulskyi et al, 2021).…”

“…For a long time, spinal cord nodes (SCN) have been particularly interested in neuromorphology (Starchenko et al, 2018;Horalskyi et al, 2020), which are afferent structures of reflex arcs and are the basis of primary centers on the way to transmit sensory information to the central system (Ernsberger, 2009), providing appropriate reactions to the action of specific factors (Medici & Shortland, 2015).…”