Affects on ultrastucture of kidney in developmental lead exposed rats

Objective: To investigate the morphological changes in kidney of developmental male rats caused by lead exposure from the level of light and electron microscopy.Method: 3-week-old male SD rats were randomly divided into control group and lead group.Rats in lead group were given 0.2% lead acetate solution by intraperitoneal injection(0.2 ml/100g body mass) once every other day,a total of 20,while rats in control group were given normal saline instead.The contents of blood lead and free protoporphyrin of rats in each group were measured at the end of the experiment.The kidneys were taken and observed through light microscope and transmission electron microscope.Results: Compared with control group,blood lead content of rats in lead group was significantly high and 6.2 times more than that in control group,while blood free protoporphyrin content of rats in lead group 3.6 times more than that in control group.Under light microscope,it was observed that glomeruli swelled,glomerulus dilatated and congested,Bowman's space narrowed,epithelium cells of proximal convoluted tubule swelled,renal tubules lumen got thinner and epithelium cells degeneratiaon and light degree of fibrosis and inflammatory cell infiltration appeared in renal interstitium.The electron microscope examination showed that glomerular capillary lumen of glomeruli in lead group slightly swelled,the lysosome in mesangial cells of glomerulus increased,Golgi complex in podocytes increased in the size and number and glomerular basement membrane(GBM) got thickening.There were two kinds of characteristic lead inclusion bodies in epithelium cells nuclei of renal tubule.There were some intranuclear concentric laminted inclusions.In epithelial cells of renal tubule,lysosomes increased,a lot of myelin bodies and autophagosomes appeared,Golgi complex swelled and rough endoplasmic reticulum got degranulation,mitochondria heteromorphosis and a typical intimal injury.Conclusion: Lead exposure could cause significant renal morphological changes.High electron density intranuclear inclusions in epithelial nuclei of renal tubular were characteristic ultrastructure of lead poisoning.