• Nazar Sahan Ivano-Frankivsk National Medical University
Keywords: chewing muscles, muscle fibers, blood vessels, links of the hemomicrocirculatory bed, hypothyroidism, ontogenesis


The aim of the study. The aim of this study was to establish the features of the structural organization of the chewing and lateral pterygoid muscles of immature rats during the developmental stages of experimental hypothyroidism.

Materials and methods. The material for the study was the chewing and lateral pterygoid muscles of 48 white mongrel immature rats-males. The following research methods were used: mercazole-induced hypothyroidism modelling, injection method for studying the bloodstream, histological examination of blood vessels and tissue elements, electron microscopy, morphometric analysis, biochemical methods, statistical evaluation of the results.

Results. A violation of thyroid homeostasis (a decrease in the concentration of thyroid hormones in the blood) has been established. In the bloodstream, edematous changes are observed histologically and submicroscopically. A decrease in the number of hemocapillaries per unit area and the number of hemocapillaries per muscle fiber have been established morphometrically. In muscle fibers, cross striation with vacuolization of endomysia and perimisia is lost. Edematous changes are observed, which are aggravated depending on the duration of experimental hypothyroidism. The glycolytic muscle fibers are more affected, and the changes are aggravated depending on the duration of the experiment. It has also been found out that there is a redistribution in the amount of muscle fibers. There is a tendency to a decrease in oxidative-glycolytic and a significant increase in glycolytic muscle fibers.

The morphological changes that have been found out are accompanied by violations of the macroelement balance, in particular, the content of Ca, P, Mg, which determine the functioning of skeletal muscle tissue.

Conclusion. Thus, at different periods of hypothyroidism, edematous changes occur both in the vascular wall and in muscle fibers, which are aggravated depending on the duration of hypothyroidism and are caused by a decrease in the basic metabolic rate, slowing of redox processes and tissue hypoxia. At the same time, chromotropic substances are released from bonds with proteins and accumulate in the intermediate substance with the subsequent replacement of collagen fibers by mucus-like masses.


Download data is not yet available.

Author Biography

Nazar Sahan, Ivano-Frankivsk National Medical University

Department of Human Anatomy


Bodnar, P. M. (2010). Endocrinology. Vynnytsia: Nova knyha, 464.

Denga, O. V., Kolesnik, K. A. (2012). The role of thyroid hormones in the integral regulation of bone metabolism in norm and in hypothyroidism (review of literature). Tavricheskiy mediko-biologicheskiy vestnik, 1, 332–337.

Danilov, N. V. (2014). Osteoporosis as a problem of thyroid surgery (literature review). Nauka molodykh, 1, 105–113.

Egorova, E. N., Vavilova, T. V., Ivanov, A. M., Kharitonov, M. A., Kalinina, N. L., Tatarkin, A. A. (2013). Study of hemostasis system parameters in patients with hypothyroidism. Saint Petersburg, 57–58.

Kovrigina, T. R., Filimonov, V. I. (2010). Differentiation of skeletal muscles of the shin in the postnatal period of ontogenesis. Morfologiya, 137 (3), 36–40.

Tambovtseva, R. V. (2014). Biochemical peculiarities of the ontogenetic development of energy supply of muscular activity. Novyye issledovaniya, 1, 68–75.

Bagarian, E. A., Lepilin, A. V., Konnov, V. V., Batusov, O. N. (2011). Changes in the function of the masticatory muscles in patients with mandibular fractures. Razvitiye stomatologicheskoy nauki i praktiki. Poltava, 61–62.

Bezzubenkova, O. E., Kurnosova, O. N. (2010). The consistency of food as a physical factor in the regulation of morphogenesis of the muscles of the jaw apparatus of rats. Morfologicheskiye vedomosti, 4, 15–24.

Kulimbetov, M. T., Rashitov, M. M., Saatov, T. S. (2009). Simulation of experimental hypothyroidism due to natural chronic iodine deficiency in the diet. International Endocrinological Journal, 2 (20), 22–27.

Charnosh, S. M. (2007). The comparative characteristic of three experimental models of hypothyroidism. Visnyk naukovykh doslidzhen, 2, 113–115.

Atamanchuk, O. V. (2012). Morphofunctional changes of tongue in experimental diabetes mellitus. Galician Medicinal Herald, 19 (4), 9–11.

Goncharov, N. P. (2011). Modern methods of hormonal analysis. Problems of Endocrinology, 57 (1), 86–91. doi:

Cardoso, L. F., Maciel, L. M. Z., de Paula, F. J. A. (2014). The multiple effects of thyroid disorders on bone and mineral metabolism. Arquivos Brasileiros de Endocrinologia & Metabologia, 58 (5), 452–463. doi:

Bodnar, P. M., Mykhalchyshyn, H. P. (2010). Iodine deficiency diseases and their prophylaxis. International Endocrinological Journal, 4 (6), 46–48.

Kaminsky, A. V., Tatarchuk, T. F. (2017). Hypothyroidism and pregnancy: new recommendations on the peculiarities of diagnosis and treatment tactics. International Endocrinological Journal, 2, 152–157.

Kozlova, L. K., Kuchma, G. B., Turmukhambetova, B. T., Ibragimova, E. A., Sokolovа, N. V., Shatilov, A. P. (2017). Complex disorders of heart rhythm and conductivity in a patient with hypothyroidism (clinical observation). Archive of Internal Medicine, 7 (6), 462–468. doi:

Dolbin, I. V., Ekimovskikh, A. Y. (2016). Hypothyroidism and ischemic cardiac disease: modern condition of the issue. Medical Almanac, 4, 121–126. doi:

Habersberger, J., Eisenhardt, S., Peter, K. (2010). C-reactive protein measurement and cardiovascular disease. The Lancet, 375 (9720), 1078. doi:

Hernández-Mijares, A., Jover, A., Bellod, L., Bañuls, C., Solá, E., Veses, S. et. al. (2013). Relation between lipoprotein subfractions and TSH levels in the cardiovascular risk among women with subclinical hypothyroidism. Clinical Endocrinology, 78 (5), 777–782. doi:

Jiskra, J. (2001). Changes in muscle tissue in hypothyroidism. Vnitr. Lek., 47 (9), 609–612.

Madariaga, M. G., Gamarra, N., Dempsey, S., Barsano, C. P. (2002). Polymyositis-Like Syndrome in Hypothyroidism: Review of Cases Reported Over the Past Twenty-Five Years. Thyroid, 12 (4), 331–336. doi:

Samsonova, A. V., Barnikova, I. E., Borisevich, M. A., Vakhnin, A. V. (2012). Methods for assessing the composition of muscle fibers in human skeletal muscles. Proceedings of the Department of Biomechanics NSU named after P. F. Lesgaft, 6, 18–27.

Sorokina, O. N. (2004). The state of masticatory muscles in modeling the mandibular deformity during the period of its active growth. Novosibirsk, 23.

Murphy, E., Williams, G. R. (2004). The thyroid and the skeleton. Clinical Endocrinology, 61 (3), 285–298. doi:

Mi, Y. F., Li, X. Y., Tang, L. J. (2009). Improvement in cardiac function after sarcoplasmic reticulum Ca2+ATPase gene transfer in a beagle heart failure model. Chinese Medical Journal, 122 (12), 1423–1428.

Murphy, E., Williams, G. R. (2004). The thyroid and the skeleton. Clinical Endocrinology, 61 (3), 285–298. doi:

👁 253
⬇ 177
How to Cite
Medicine and Dentistry