The Investigation On The Renal Injury And Effects On Oxidative Stress Of Guinea Pigs Induced By Trichloroethylene

Background Trichloroethylene (TCE) is an organic solvent mainly used as degreaser in industry. Occupational exposing to TCE, workers appear dermatitis (DMLT) with poly-organ injury, and it has become a major occupational health issue now. In recent years, there are many studies on the mechanism of skin and liver injury, but there are little studies on the mechanism of renal injuryObjective Detecting MDA, SOD, ALB,α1-MG,β2-MG,γ-GGT and AAP expression of Guinea Pigs in different groups and different time points, combined with renal function tests and pathological examination, to investigate the mechanism of renal injury induced by TCE.Method Female guinea pigs, which were white and weighing 250～300g ,were adopted. After adaptive feeding a week, the Guinea Pigs were divided to blank control group, solvent (olive oil) control group, DNCB control grouTCE group in random. To monitor the status of guinea-pig growth and health, their weight was measured regularly. Adopting Guinea Pig Maximization Test (GPMT) to establish sensitization model, to observe and record the skin reaction in Guinea Pigs back and take pictures. Reaction in Guinea Pigs skin was scored in accordance with the skin reaction score standards in"Toxic chemicals identified technical specifications"(the Ministry of Health superintend made【2005】No.272). When the skin reaction scores of test group≥1, it should be ruled positive skin sensitization, which was sensitized group, otherwise was non-sensitized group. 24h before, 24h and 72h after sensitization test and collected total volume urine of Guinea Pigs,suctioned the serum and killed the animals. Serum was prepared for renal function. Urine protein and urease were detected by ELISA. MDA and SOD in renal homogenate were determined by chemistry. Experimental results were analyzed with SPSS15.0.Result1. Sensitization rate In the skin sensitization test, the control group, solvent control group showed no erythema or edema; 17 of 26 animals in TCE test group showed erythema and edema, sensitization rate is 65.38%.All animals in DNCB control group showed erythema and edema.2. Pathological test results The kidneys of the normal control group exhibited normal cortical morphology as determined by light microscope and electron microscope.By HE staining and electron microscope, TCE sensitized group was observed segmental glomerular basement membrane thickening or meager, some fusion of foot processes, tubular epithelial cell mitochondrial swelling, vacuolar degeneration and atrophy of microvilli, individual tubules were Atrophy-like.3. Results of liver function Compared with the control group, renal function of solvent group was not statistically significant (p>0.05); Compared with the solvent control group and TCE non-provocated group,BUN level in TCE sensitized group elevated significantly (p<0.05); Compared with TCE non-sensitized group, BUN level in TCE sensitized 24h and 72h group increased significantly(p<0.05) ; Compared with DNCB control group,BUN levels in TCE sensitized 24h group increased significantly(p<0.05) . Compared with the solvent control group, Cr level in TCE sensitized group showed no significant difference(p>0.05),but increased significantly compared with the DNCB control group.4. Results of mALB Compared with the blank control group, mALB level in solvent control group showed no significant difference(p>0.05); Compared with the solvent control group, mALB in TCE exposured group elevated significantly(p<0.05); mALB were significantly increased in TCE sensitized group compared with TCE non-sensitized group or TCE non-provocated group (p<0.05);Compared with DNCB control group,mALB in TCE sensitized and non-sensitized group both increased significantly (p<0.05).5. Results ofα1-MG Compared with the blank control group,α1-MG levels in solvent control group showed no significant difference (p>0.05); Compared with the solvent control group or TCE non-provocated group,α1-MG levels in TCE sensitized and non-sensitized group both increased significantly (p<0.05); Compared with TCE non-sensitized group,α1-MG levels in TCE sensitized 72h group increased significantly (p<0.05);α1-MG levels were significantly increased in TCE sensitized 24h group compared with DNCB control group (p<0.05).6. Results ofβ2-MG Compared with the blank control group,β2-MG levels in solvent control group showed no significant difference (p>0.05); Compared with the solvent control group,TCE non-provocated group or DNCB control group,β2-MG levels in TCE sensitized group increased significantly (p<0.05); Compared with TCE non-sensitized group,β2-MG levels in TCE sensitized 24h increased significantly(p<0.05).7. Results of AAP Compared with the blank control group, AAP levels in solvent control group showed no significant difference (p>0.05); Compared with the solvent control group, DNCB control group or TCE non-sensitized group, AAP levels in TCE sensitized group increased significantly (p<0.05); Compared with TCE non-provocated group, AAP levels in TCE sensitized 24h group increased significantly(p<0.05).8. Results of Y-GGT Compared with the blank control group, Y-GGT levels in solvent control group showed no significant difference (p>0.05); Compared with the solvent control group, Y-GGT levels in TCE non- provocated group and TCE sensitized group increased significantly (p<0.05); Y-GGT were significantly increased in TCE sensitized group compared with DNCB control group (p<0.05).9. MDA and SOD The content of MDA in kidney of the TCE sensitized groups were increased (p<0.05) at the point of 24h, while T-SOD activity decreased significantly (p<0.05) at the all time. At the point of 24h, the content of MDA in kidney of the TCE sensitized groups were higher than those in no-sensitized groups (P<0.05). Compared with no-sensitized groups, the T-SOD activity decreased significantly at the point of 24h and 72h.Conclusion1. TCE sensitized model was established by Guinea Gigs Maximum Test, TCE sensitization rate was 65.38%.2. TCE can cause renal pathological damage and renal function injury; TCE-induced kidney damage in guinea pigs are not limited to glomeruli, but also involving the renal tubules, and the renal tubular damage was severe in the glomeruli. 3. Urinary protein and urinary enzymes may be used as independent factors,combined with oxidative stress,may have participated in renal injury induced by TCE.4. In the mechanisms of renal injury,TCE is different from DNCB;TCE is not only a simple allergic agent, but also is immune damage agent.