Effect of selenium supplementation on the structure of the lung of adult albino rats subjected to experimentally induced chronic renal failure

Introduction :The relationship between the lungs and the kidneys is clinically important during both healthy and diseased states. Aim of the study :The aim of the study was to demonstrate the histological effect of chronic renal failure (CRF) on the structure of the lung and determine whether selenium could ameliorate these effects. Materials and methods :Adult rats were divided into three groups. Group I was the control group. Rats in group II were subjected to five-sixth nephrectomy to induce CRF. Rats in group III were subjected to five-sixth nephrectomy and then supplemented with sodium selenite at a dose of 1 mg/kg twice daily for 10 weeks by oral gavage. Blood samples were collected to measure the levels of hemoglobin and serum creatinine. At the end of the experiment, specimens from the lung were taken and prepared for immunohistochemical staining and light and electron microscopic study. Results :In group II, the bronchiolar walls were found to be thickened and surrounded by marked aggregations of mononuclear cells. The epithelium lining some of them was degenerated and most of their nuclei were pyknotic. The interalveolar septa were thickened by mononuclear cellular infiltrations. In addition, many fibroblasts and numerous deposited collagen fibers were noticed by electron microscopic examination. Many empty spaces, red blood corpuscles, and acidophilic exudates were also seen. There was a significant increase in the mean number of type II pneumocytes in comparison with the control group and most of the type I pneumocytes showed darkly stained nuclei. In addition, strong positive immune reactions for caspase-3 were also observed along the alveolar walls and in the endothelium lining some of the blood vessels. Group III revealed a relative improvement in the structure of the lung. There was a significant decrease in serum creatinine and a significant increase in hemoglobin content in comparison with group II. Conclusion:Selenium supplementation can improve the structure of the lung and biochemical profile in models of experimentally induced CRF.