Anatomical and topographic characteristics and cytoarchitectonics of the trigeminal node in an adult

Introduction. In numerous domestic and foreign sources, structure of the trigeminal node of human and animals have been studied from topographic, anatomical, histological, embryological, surgical, neurophysiological and pathoanatomical positions. It is known, the shape of the trigeminal node is variable, most authors believe that it has a semilunar shape. The internal structure is mainly reduced to the characteristics of the cellular component of the node, as well as the nerve fibers passing through it. In the human trigeminal ganglion, the ratio of neurons to glia is 1:100. It is believed that a Gasser node can contain from 20 to 35 thousand neurons. In addition, the node contains fibroblasts, as well as small vessels, mainly blood capillaries. The aim of the study is to clarify the anatomical and topographic characteristics and structural organization, as well as the morphometric features of trigeminal neurons.
Materials and methods. The object of the study was 4 trigeminal ganglia with a sensitive root and branches extending from it, with preserved dura mater, taken from corpses of adult men of the second period of adulthood (60-65 years old), without signs of surgical interventions and injuries. Sections were made from the selected material, stained according to the Nissl, Van Gieson methods, as well as with hematoxylin and eosin.
Results. In accordance with the peculiarities of the structural organization, the structural and functional zones of the constituent parts of the Gasser node (the trifurcation zone, the intermediate zone of the trigeminal node, the zone of formation of the sensitive root) are isolated. Attention is drawn to the highest density of distribution of neuron bodies oriented in the direction of the maxillary and mandibular branches of the trigeminal nerve, which, as we assume, is explained by the larger area of receptive fields associated with these branches. In the zone of formation of the sensory root are seen mainly large neurons, divided into groups by nerve fibers, forming bundles of orders I, II and III, which merge to form a sensitive root.
Conclusions. The trigeminal ganglion is characterized by local features of neurocyto- and myeloarchitectonics, the study of which should be carried out taking into account gender and age characteristics.

1. Sudarikova T.V., Trufanov I.N., Gorskaya T.V. and others. Typical, sexual, and age-related features of the topography of the human trigeminal node. The successes of modern natural science. 2006; 3: 53–54. (In Russ).

2. Chekhonatsky A.A., Skulovich S.Z., Ushakov D.A. and others. Puncture access to the sensitive trigeminal nerve root: anatomical and topographic features (overview). Saratov Scientific and Medical Journal. 2012; 8 (3): 785–790. (In Russ).

3. Bernard F., Mercier P., Sindou M. Morphological and functional anatomy of the trigeminal triangular plexus as an anatomical entity: a systematic review. Surgical and Radiologic Anatomy. 2019. doi.org/10.1007/s00276-019-02217-8

4. Bond J.D., Xu Z., Zhang H. et al. Meckel’s Cave and Somatotopy of the Trigeminal Ganglion. World Neurosurgery. 2021; 148: 178–187. doi.org/10.1016/j.wneu.2021.01.081

5. Boyer N.P., Tang P.H., Higbee D. et al. Lipofuscin and A2E accumulate with age in the retinal pigment epithelium of Nrl-/- mice. Photochemistry and Photobiology. 2012; 88(6): 1373–1377.

6. Brunk U.T., Terman A. The mitochondrial-lysosomal axis theory of aging. European Journal of Biochemistry. 2002; 269(8): 1996–2002.

7. Di Guardo G. Lipofuscin. Lipofuscin-Like Pigments and Autofluorescence. European Journal of Histochemistry. 2015; 59(1): 2485.

8. Gray D.A., Woulfe J. Lipofuscin and Aging: A Matter of Toxic Waste. Science of Aging Knowledge Environment. 2005; 2005(5): re1.

9. Markelic M., Velickovic K., Golic I. et al. The origin of lipofuscin in brown adipocytes of hyperinsulinaemic rats: the role of lipid peroxidation and iron. Histology and Histopathology. 2013; 28(4): 493–503.

10. Messlinger K., Russo A.F. Current understanding of trigeminal ganglion structure and function in headache. Cephalalgia. 2019; 39(13): 1661–1674. doi.org/10.1177/0333102418786261

11. Papaevgeniou N., Hoehn A. et al. Lipofuscin effects in Caenorhabditis elegans ageing model. Free Radical Biology and Medicine. 2017; 108: 48–56.

12. Reva I.V., Reva G.V., Yamamoto T. and others. Features of hypothalamic neurons in cerebral ischemia. Fundamental research. 2014; 4 (part 3): 593-600. (In Russ).

13. Nikiforov A.G., Starchenko I.I., Chernyak V.V. Features of the cellular composition of human spinal nodes in old age. The world of medicine and biology. 2013; 2-2 (38): 64–66. (In Russ).

14. Kurz T., Terman A., Gustafsson B. et al. Lysosomes in iron metabolism, ageing and apoptosis. Histochemistry and Cell Biology. 2008; 129(4): 389–406. doi.org/10.1007/s00418-008-0394-y