HISTOLOGICAL STRUCTURE OF FEMORAL BONE TISSUE IN ADULT MALE RATS AFTER SUBCHRONIC PERORAL ADMINISTRATIONS OF CADMIUM AND SELENIUM

The aim of this study was to examine effects of subchronic peroral administrations of cadmium and selenium on femoral bone microscopic structure in adult male rats. 1-month-old male Wistar rats were randomly divided into three groups, each containing 10 males. In the first group (EG1), rats were administered by cadmium at the dose of 30 mg of CdCl2/L in drinking water for 90 days. In the second group (EG2), animals received a drinking water containing 5 mg of Na2SeO3/L for the same treatment period. The third group of rats without cadmium and selenium applications, served as a control group (CG). At the end of the experiment (90 days), all animals were killed and their right femora were collected for microscopic evaluation. We found that the qualitative histological characteristics of the compact bone tissue were different in the middle part of compact bone in medial and lateral views between experimental (EG1, EG2) and control groups (CG). In Cd- and Se-treated rats, a smaller number of primary and secondary osteons was identified. Moreover, a few resorption lacunae were observed in rats perorally exposed to Cd (EG1). Histomorphometric evaluation showed a significant decrease (P<0.05) in all variables (area, perimeter, maximum and minimum diameter) of the primary osteons' vascular canals in the Cd-exposed rats (EG1) as compared to the control group. In comparison with the group CG, they were significantly increased (P<0.05) in the Se-exposed rats (EG2). Values of the Haversian canals and secondary osteons were significantly decreased (P<0.05) for all variables in rats from both experimental groups (EG1, EG2) as compared to the control (CG). The results allow for the conclusion that subchronic exposure to Cd and Se at the levels used in this study significantly influenced microscopic structure of femoral bone tissue in adult male rats.