The expression of NF-κB and TGF-β1 in the injured kidneys of neonate rats with endotoxemia

Objective To investigate the mechanism of the kidney injure in the newborn rats with endotoxemia.Methods Eighty Wistar rats aged 7 days were randomly divided into 2 groups:control group (intraperitoneal injection of saline of 0.1 ml;n = 40),lipopolysaccharide(LPS) group(intraperitoneal injection of LPS of 5 mg/kg;n =40).The rats in either group were killed at 1 h,4 h,8 h and 12 hours after intraperitoneal injection,respectively.The expressions of NF-κB and TGF-β1 in the kidney were detected by using the immunohistochemical assay.Renal ultrastructural changes was observed with a CM100 Philips electron microscope.Results The NF-κB in control group had no expression.NF-κB in LPS group mainly expressed in the renal tubular epithelial cell,increased at 1 h after test and peaked at 8 h,and slightly descended at 12 h.The expression of TGF-β1 in control group was slight,and had not show significant difference from control group at 1 h,4 h and 8 h,but significantly higher than that in control group at 12 h.In LPS group,newborn rat renal glomerular basement membrane was complete,part epithelial cell foot processes were fused and renal tubules epithelial cell mild mitochondria vacuolization was found at 4 h.Renal glomeruli epithelial cell foot processes obvious confluenced,quantities of mesangial cells mitochondria vacuole,and renal tubules epithelial cell mitochondria expanded to bubbles at 12 h.Conclusion The NF-κB involves in the pathogenesis of kidney damage induced by endotoxemia,but TGF-β1 may help to repair the damaged kidney,and may repress the production of NF-κB. Key words: Endotoxemia; Kidney injury; Nuclear factor-κB; Transforming growth factor β1