IMMUNOHISTOCHEMICAL CHANGES OF HIPPOCAMPAL MICROGLIAL CELLS IN CHRONIC NEUROINFLAMMATION

Abstract

The article provides information about a research study conducted to investigate the changes in hippocampal neuroglial cells resulting from various neuroinflammatory processes. The model of chronic brain inflammation was created by intraperitoneal injection of Escherichia coli lipopolysaccharide (LPS) at a dose of 0.75 mg/kg body weight to white mice for 7 consecutive days. Histological sections were obtained from brain sections of experimental animals 10 weeks after LPS injection. Both thin sections stained with hematoxylin and eosin and semi-thin sections stained with toluidine, as well as immunohistochemical studies against the IBA-1 antigen, showed that the total number of microglial cells located in the hippocampus and prefrontal cortex of the cerebral hemispheres increased. These cells were located in clusters in perivascular zones and near degenerating neurons. Morphological analysis showed that most of the cells corresponded to the phenotype of activated microglia M1. The results show that, even though ten weeks have passed since the creation of the systemic inflammation model, the ongoing activation of the immune system and neuroinflammatory reactions in the brain tissue indicate that the process has become chronic. This creates favorable conditions for the development of various neurological and neurodegenerative diseases.