Morphological characteristics of the gastrointestinal tract under subchronic exposure to nano-dispersed manganese oxide (III, IV)

A study of morphological characteristics of the gastrointestinal tract in laboratory animals during a subchronic (over a 30 day period) intra-gastric administration of the aqueos suspension of nano-dispersed manganese oxide (III, IV) at a dose of 10.4 mg/kg demonstrated a complex of pathomorphological changes. These included an evenly distributed moderate inflammatory response in the mucosal and submucosal layers of the stomach and in the small and large intestines, which was manifested via lymphocyte and macrophage infiltration admixed with eosinophils and plasma cells. In the ganglia of the intermuscular nerve plexus, dystrophic changes with a pronounced perneural edema were observed. When a microfine equivalent was administered in a similar way, the inflammatory response in the studied organs was local and mild. No events of perneural edema or dystrophy in the ganglia of the intermuscular nerve plexus were detected.