The role of adipose tissue in the healing of rat uterine wall after a full-thickness surgical incision

Introduction. Data about the role of components of adipose tissue in the repair of damaged uterine walls are limited, although a number of authors claim that cell-based drugs from adipose tissue have a positive effect on the repair of damaged uterine walls in laboratory rodents. Meanwhile, stem cells derived from adipose tissue are considered to be the most promising type of cells in regenerative medicine. The aim of the studywas to evaluate the adipocyte components in the uterine wall of rats in healing after a full-thickness surgi-cal incision. Materials and methods. We conducted the study on 40 female Sprague Dawley rats. The animals were sub-jected to a full-thickness longitudinal incision in the wall of the right uterine horn, with the left one serving as an intact control. We carried out morphological examinations of the uterine walls daily in 5 animals from day 1 to 7 and on day 15. The sections from paraffin blocks were stained with hematoxylin and eosin and Mallory’s trichrome staining. Immunohistochemistry detected FABP4+ adipocytes and CD68+ macrophages. The morphometric study was carried out using the Leica system (Leica, Germany). The results underwent processing in the Statistica 12 software (StatSoft). Results. We noticed the period of the most active interaction of adipose tissue with the damaged horn to last from day 3 to 15 and coincide with the macrophage activation in the healing zone. The intact left uterine horn was not involved in the interaction processes with the mesenteric adipose tissue. Starting from day 3 FABP4+ cells in the uterine wall of the operated horn formed groups, creating rounded nest-like structures. Clusters of FABP4+ cells were localized in the healing zone, near the suture material, and in the perime-trium near the mesentery attachment sites. The changes over time of the indicators of the area of cell nests depended on the localization and duration of healing. There were no FABP4+ cells in the left intact horn. Conclusion. We characterized the morphological interaction of adipose tissue with the damaged uterine wall during the first two weeks after a full-thickness surgical incision of the rat uterine horn. The results of the study indicate that adipocytes take an active part in the healing after a surgical incision of the rat uterine wall at the earliest stages. Keywords: rat uterus, hysterotomy, healing, adipocytes, macrophages