Tissue and ultrastructural analysis of the liver of prepubertal rats under subtoxic exposure to cadmium and lead

Abstract

Using light and electron microscopy, the effect of intoxication with cadmium sulfate (Cd) and lead acetate (Pb) for 3 weeks on the architectonics of the liver parenchyma and ultrastructural features of hepatocytes of 40 prepubertal male Wistar rats was studied, taking into account the model of the classical hepatic lobule. Animals were divided into 4 groups: 1st – control; 2nd – cadmium sulfate solution at a dose of 0.5 mg/kg; 3rd – lead acetate solution 10 mg/kg; 4th – a combination of these solutions. According to stereological analysis of semi-thin sections, statistically significant indicators of periportal zones reflect an increase in the volume of hepatocytes when exposed to Cd (2nd and 4th groups). In all groups, with the exception of the 3rd one (Pb), an increase in the parenchymal compartment in the porto-central gradient was revealed, indicating the formation of hepatocellular ballooning. In all experimental groups, for the periportal zone of the hepatic lobule, a characteristic feature of the ultrastructure of hepatocytes was a statistically significant decrease in the volumetric density of the endoplasmic reticulum; for the centrilobular zone – of mitochondria; for the perivenular zone – mitochondria and nuclei of hepatocytes. The formation of autophagosomes with signs of predominantly mitochondrial utilization attracted attention in groups exposed to Pb. Pathological changes are compensated by increased transsinusoidal metabolism and complexes of biosynthesis organelles.