Mechanism of damage to platelet and erythrocyte hemostasis in rats with prolonged hypokinesia

Abstract

The aim of the study was to determine the morphological changes in the cellular elements of blood in rats of different ages under conditions of prolonged hypokinesia. Research into the structural and functional properties of platelets and erythrocytes was carried out by electron microscope and by biochemical methods in 90 mature male rats aged 2, 12 and 24 months. We found that in young (2 month animals) there was a significant increase in the relative content of activated platelets while the normal content of aggregated and degranulated forms with the appearance of single platelets was maintained with an imbalance of alpha and delta granules. In 12-month-old animals, platelet hemostasis disorders were manifested by a significant increase in the relative content of activated platelets (by 125.8–134.7%) with an increase in aggregated and degranulated forms, the appearance of numerous platelets with an imbalance of alpha- and delta-granules, and reduction of mitochondria (by 24.9–27.8%). In 24 month old animals there was a sharp violation of platelet hemostasis due to a significant increase in the content of activated, degranulated and aggregated platelets, the release of the majority of granules, the development of intravascular platelet hyperactivation, an increase in the number of reversible and irreversibly transformed erythrocytes, an increase in the level of aggregation, in particular the appearance of complex cellular aggregates and bizarre forms of red blood cells. The greatest degree of manifestation of morpho-functional changes was revealed in animals aged 24 months, with relative stability of the hemostasis system in 2 and 12 month old animals. Our results showed that irrespective of age, the degree of disturbance of platelet-erythrocyte hemostasis rose as the period of hypokinesia increased and also depended on the increase in the level of serum creatinine. Taken together, intravascular platelet hyperactivation, an imbalance in the content of all types of granules, the transformation of surface cytoarchitectonics of erythrocytes, and the formation of platelet aggregates may play the role of an early predictor of the development of hypokinetic disease

Keywords

• hypokinesia
• blood platelet
• erythrocytes
• hemostasis
• ultrastructure