ANATOMICAL AND HISTOLOGICAL ASPECTS OF THE UTERINE STRUCTURE IN ALBINO RAT

Objective - to study anatomo-histological structure of the uterus in albino rat. Material and methods. Body, cervix and horns of the uterus were examined in 10 nulliparous mature albino rats. Four-μmthick paraffin sections were stained with hematoxylin and eosin. The myocytes were studied using immunohistochemistry with the monoclonal antibodies against α-smooth muscle actin; electronic transmission microscopy and morphometry. Results. The rat uterus is formed by partial merging of walls of the right and left uterine horns in the caudal portion. As a result, a median septum is formed, separating two not clearly demarcated cavities of the uterine body and cervix that open into the vagina with separate ostia. Only perimetrium and part of the myometrium are involved in the fusion, namely, the supravascular and vascular muscle layers. In the cervix, the inner layer of the myometrium forms a circular sphincter. It is consists of smooth muscle tissue, in which small and medium myocytes prevail, possibly indicating a high potential of cells for their further differentiation. The epithelium of the endocervical mucosa in rats structurally resembles that one in humans. Conclusions. A bicornuate uterus is characteristic for rat. The obtained data on the structure of the uterus can be used to conduct research on the reactivity of uterine tissues to experimental influences and on their regeneration.

uterus, cervical sphincter, myometrium, smooth myocytes, albino rat