A Study Of Melamine's Chronic Toxicity On The SD Rat Kidney

ObjectiveThe research established the rat model of toxic melamine,and to investigate the damage on the kidney cell under melamine.MethodFifty-six SD rats were separated four groups:high concentration group(A), medium concentration group(B),low concentration group(C) three groups with different concentrations of melamine and the control group(D group),each group has 14 rats.We administered those 7-10 days of newborn SD rats one month,after the animals were killed,their blood was sent to examine blood urea nitrogen,creatinine, uric acid,calcium,in order to understand the renal function,the kidney tissue were respectively observed the renal micro-structural changes under the light microscope and the electron microscopy,and used quantitative analysis of images.The experimental results were analyzed with SPSS11.0 statistical software,p＜0.05 were statistically significant.Results1.On autopsy,kidney volume of experimental mice are slightly larger than that of the contrast mice.2.under the electron microscopy,the experimental group shows that electron-dense deposited in basement membrane,the micro-structure of cells changed and inflammatory cell infiltrated,these changes were most pronounced in group A,secondary in group B,least in group C,in the control group D did not see electron-dense material; 3.The kidney of experimental rats have different degrees of pathological changes under the light microscope,group A was more pronounced,with pathological image analysis results of the experimental group,glomerular cross-sectional area was only smaller than the control group,the other indicators(glomerular diameter,proximal tubule diameter,distal convoluted tubule diameter),experimental group and control group were not significantly different, stones and crystals were not found in all specimens under the light microscope;4.The weight of the experimental groups has no significant difference from the control group;5.Besides there were significant differences in blood urea nitrogen of group A, and group C from the control group D,the other biochemical indicators of the experimental group has no difference from the control group;ConclusionThere are different degrees of kidney damage under the different concentration levels of melamine,these injury is mainly the changes of kidney tissue micro-structure,but they have no indicators of renal function and biochemical changes,and have no clear stones and calculus.