Regeneration of muscle tissue of the external anal sphincter in experimental androgen deficiency

The aim of the study was to estimate the dynamics of reactive changes and regeneration processes of the muscle tissue of the external anal sphincter in rats under conditions of physiological norm and with androgenic insufficiency. Material and methods. The study was carried out on 40 mature laboratory male rats, which were divided into 3 groups: 1 – intact control group; 2 – control group, with damage to the external anal sphincter in animals with physiological testosterone levels and 3 – experimental, with simulated postnatal hypogonadism and damage to the sphincter. To assess reparative regeneration, material after damage was taken on days 3, 5, 7, 14, 21 and 30. Histological sections were stained with hematoxylin and eosin, as well as IHC-staining using monoclonal antibodies to the cell proliferation marker ki-67. Ultramicroscopic preparations were obtained according to standard preparation protocols. Digital data obtained during the morphological study were subjected to statistical processing. Results. Morphological changes that occur in muscle tissue against the background of androgen deficiency are more pronounced than with physiological testosterone levels. This manifests itself in more intense interstitial edema, prolongation of muscle fibers destruction and processes of post-traumatic inflammation. As a result, in the experimental group the formation of new muscle fibers slows down, and the wound space is filled with scar connective tissue, the volume of which is 10% greater than with physiological testosterone levels. Conclusion. Against the background of androgen deficiency, the mechanisms of reparative regeneration of the muscle tissue of the external anal sphincter are not violated, however, hypogonadism is a factor that enhances inflammatory processes and inhibits the process of muscle tissue recovery.