The Nephrotoxicity Study Of LianBiZhi Injection In SD Rats

Objective To investigate the toxic response, the pathological changes of the nephrotoxicity of LianBiZhi injection in SD rat with different time and dosage and to identify the non-toxic dosage; observe apoptosis in rats renal tubule epithelial cell and to explore its meaning in the mechanism of renal toxicity induced by LianBiZhi injection. Methods Healthy adult Spragne-Dawley rats(170±20g,♀∶♂=1∶1) were divided randomly into three groups(n=42 per group): LianBiZhi injection group at the dosage of 700mg/kg/d(LianBiZhi injection group A), 300mg/kg/d (LianBiZhi injection groupB), the N.S. control group by i.p. once a day, respectively. On the Day 10, Day 20 and Day30, fourteen rats(♀∶♂=1∶1) in each group were sacrificed. The following indices were observed and determined: clinical signs, body weight growth, the haematology, clinical chemistry, urine NAG, urineβ₂-MD, gross necropsy and histopathology. Apoptosis was detected with TUNEL. Result (1) In LianBiZhi injection groupA(300mg/kg/d), the level of BUN and Scr in blood, the level of NAG,β₂-MD, protein in urine showed no statistical differences compared with control group( P>0．05) . Renal morphology was no obvious changes at day 10, 20, 30．(2) In LianBiZhi injection groupB(700mg/kg/d), the level ofβ₂-MD in urine increased at the day10, 20 and 30 compared with control group( P<0．05) . The level of BUN and Scr in blood, the level of NAG, protein in urine showed no statistical differences compared with control group( P>0．05) . 10, 20, 30 days, urineβ2-MD compared with the control group was significantly higher (P <0．05) . Urine glucose significantly increased in 30 days compared with the control group (P <0．05) . Light microscopy shows some rats (20/42) renal tubular epithelial cells edema, interstitium edema and hemorrhage at corticomedullary junction, cortical renal tubules degeneration, renal tubular epithelial cells in a flat, brush border disappearance, interstitial lymphocytes and monocyte infiltration, lesions with prolonged administration heavier. Furthermore, the degree of kidney damage showed some differences in gender and male rats were more serious compared with female rats (P <0．05) . Electron microscope showed tubular epithelial cells edema, mitochondria swelling, interstitium edema, lymphocyte infiltration, fibrous tissue hyperplasia. See early apoptosis of renal tubular epithelial cells. (3) 10, 20, 30 days, LianBiZhi injection groupB(700mg/kg/d) renal tubular epithelial cell apoptosis count compared with the control group significantly increased (P <0．05) . Apoptosis cell counting and pathological grading is positively correlated, that is, the more serious the disease, the more apoptotic cells. Conclusion LianBiZhi injection induced SD rat renal toxicity is time-dose related. In 700mg/kg/d dose, injury is part of tubules and interstitium at corticomedullary junction or nearly renal cortex. With the extension of administration, kidney damage even heavier. In this study, the safe dose for the reference range is following 300mg/kg/d. SD rats renal toxicity aroused by LianBiZhi injection has gender differences, male injury being more serious. Cell apoptosis mechanism may be involved in the nephrotoxicity induced by LianBiZhi injection.