Introduction. In recent decades, a new type of adipose tissue has been identified. Because of their external structure and location, these adipocytes are called beige adipocytes. It is believed that beige adipocytes originate from brown adipocytes, which are located in depots of white adipose tissue. In the literature, there is a single piece of information on the peculiarities of the formation and topography of adipose tissue in human fetuses of various ages.
The objective of the study was to assess the peculiarities of the structure and distribution of adipose tissue of the lower leg in human fetuses of 5-8 months.
Materials and methods. Microscopic examination was carried out on preparations of the leg region of 18 human fetuses 136.0-310.0 mm parietal-coccygeal length (PCL) without external signs of anatomical deviations or anomalies in the development of bone, fascial-muscular and vascular-nervous structures of the lower extremities.
Results. The composition of adipose tissue in the examined human fetuses of different gestational periods is heterogeneous and is represented by unilocular and multilocular cells united in clusters of different shapes. During the fetal stage, the number and ratio between the types of fat cells change.
Conclusions. Adipocytes are located singly in 5-month-old human fetuses, in 6-month-old fetuses they form elongated clusters, and from the end of the 7th to the beginning of the 8th month of the fetal period of ontogenesis, adipocytes form plaque-like structures located in several rows. The lowest number of fat cells is observed in 5-month-old human fetuses, among which the percentage of multilocular cells is 85.3±0.92%. In 6-month-old human fetuses, the ratio of multilocular cells to unilocular cells is 93.0±0.12%; in 7-month-old fetuses – 72.7±0.16%; in fetuses of 8 months of gestation – 57.8±0.17%.
Keywords: multilocular cell, unilocular cell, beige adipocyte, adipose tissue, fetus.
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Tatiana V. KHMARA
Human Anatomy Department, Bukovinian State Medical University, Chernivtsi, Ukraine
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