Peripheral blood and haematopoiesis in bone marrow and liver tissue were investigated in Bufo bufo during the sexual cycle. A combined touch and imprinting tissue method were applied for the haematopoietic cell isolation. The liver is the primary site of erythropoiesis and partial lymphopoiesis. There was a positive correlation between body mass and liver mass, but it was not significant (P > 0.05). The primary role of yellow bone marrow is the maturation of haematopoietic cells, while red bone marrow is responsible for the production of blood cells. The largest surface, and therefore the largest dimensions, was established for erythrocytes. Significant differences in the number of leukocytes and their size were established between males and females (P < 0.05). Small numbers of leukocytes but very large cells were characteristic for females. The highest percentages of leukocytes were for lymphocytes and eosinophils. The reproductive period showed significant impact on the haematopoietic intensity in the bone marrow and liver, resulting in changes in peripheral blood, regarding the ratio of mature blood cells.

No abstract

Emperipolesis is considered a physiological phenomena often present in various pathophysiological conditions, but its etiology is still unknown. In this study, we analyzed the number of megakaryocytes and the percentage of emperipoletic cells in the sternal and femoral bone marrow of Wistar rats. Five types in the thrombopoiesis lineage (megakaryoblasts, promegakaryocytes and megakaryocytes - acidophilic, basophilic and thrombocytogenic) were determined. Except for basophilic megakaryocytes, significant differences were found for number of thrombopoietic cells in the sternal and femoral bone marrow. A larger number of thrombocytogenic megakaryocytes were present in the sternal bone marrow. Emperipoletic cells were significantly present in the femoral compared to the sternal bone marrow. Emperipolesis was typical for lymphocytes and neutrophils individually, while emperipolesis with two or more cells within thrombopoietic cell was also present (1-7 %) and significant differences between the sternal and femoral bone marrow were detected. Emperipolesis was found in all analysed rats and it most commonly occured within mature megakaryocytes and rarely megakaryoblasts, while it was not recorded in the promegakaryocytes. The high incidence of megakaryocytes with emperopolesis in rats could be a consequence of “normal” cell retention in the cytoplasm of megakaryocytes while passing blood cells to circulation or related to haematopoietic response due to high incidence of inbreeding.

No abstract