Characteristics And Changes Of Kidney In Premature Mice And Its Susceptibility To Renal Damage Induced By Adriamycin In Adulthood

Objective: To observe the characteristics of premature mice kidney and to explore its changing trend, and its susceptibility to renal damage induced by adriamycin in adulthood.Methods: 1. Characteristics and changes of kidney in premature mice: The mice were divided into two groups. premature mice. delivered 4 days early, and full day mice, delivered on days 21 in pregnancy. 18 mice in each group. Birth length and birth weight of the two groups were observed, and kidney weight/body weight ratio,urinary albumin/ creatinine ratio (ACR), serum creatinine (Scr), and blood urea nitrogen (BUN) were observed at the time of the 4th week, the 8th week and the 12th week after birth. The different renal pathology of two groups were observed under light microscope and electron microscope, western blot detect the difference of VEGF,VEGFR2 and podocyte marker WT1 in renal tissues of two groups, and immunohistochemical staining of WT1 was also observed.2. Premature mice susceptibility to renal damage induced by adriamycin in adulthood: The 8 weeks old mice were divided into four groups: full day group,premature group, full day + adriamycin group and premature + adriamycin group.Urinary ACR, Scr,and BUN were observed in four groups after injecting adriamycin at 1, 2,4,8,and 12 weeks. The different renal pathology of four groups were observed under light microscope and electron microscope, western blot detect the difference of VEGF, VEGFR2 and podocyte marker WT1 in renal tissues of four groups, and immunohistochemical staining of WT1 was also observed.Results: 1.Characteristics and changes of kidney in premature mice:(1) comparing with the full day mice, the premature mice length and weight decreased significantly;(2) At the age of 4 weeks, the premature mice kidney weight and body weight ratio was significantly decreased, urinary ACR was significantly increased. At 8 and 12 weeks, there was no significant difference in two groups kidney weight and body weight ratio, urinary ACR, Scr and BUN in tow groups; (3) comparing with the full day mice, VEGF and VEGFR2 expression was significantly increased in the kidney of premature mice, WT1 expression was significantly decreased.2. Premature mice susceptibility to renal damage induced by adriamycin in adulthood: (1) Compared with full day + adriamycin group,premature + adriamycin group mice urinary ACR, Scr and BUN increased significantly early (premature +adriamycin group mice urinary ACR, Scr and BUN increased significantly at the first week, full day + adriamycin group began to rise at the second week), and the degree of injury was more serious; (2) Electron microscopy showed that the early stage of the foot fusion appeared earlier and more severe in the premature+adriamycin group mice;(3) Compared with the full day + adriamycin group , premature + adriamycin group VEGF and VEGFR2 expression was up-regulated in the kidney of and WT1 expression was decreasing, the number of glomerular WT1 positive podocytes decreased significantly.Conclusion: 1. Premature mice were born at low birth weight and length, with transient proteinuria and decreased glomerular podocyte numbers, suggesting renal dysplasia and urinary protein improves with age. Premature mice increased VEGF,VEGFR2 expression, and decreased WT1 expression may be associated with renal damage.2.The susceptibility of premature mice-adriamycin is increased,which may be related to its renal dysplasia...