Experimental Study About Protective Effect Of Tea Polyphenols Against Renal Ischemia-reperfusion Injury Of Rats

Objective:To investigate the mechanism of action of the high effective antioxidation drug tea polyphenols antagonise ischemic reperfusion injury by intra-venous injection through establishing the model of ischemic reperfusion injury on monolateral kidney.Methods:1.The grouping 30 experimental SD rats,the weight 260±20g, randomly assingment these rats to :A.high dose tea polyphenols gopup(TP 100mg/kg), B.low dose tea polyphenols gopup(TP 50mg/kg), C.vitamin C group(vitC 200mg/kg), D.the ischemic reperfusion injury group ,E.false operation group ,6 rats each group. A,B,C groups inject corresp. drugs through left femoral vein 10 minutes before reperfusion, intravenous inject- tion for 1 minute. 2. Establish of the model 10% chloral hydrate (3ml/kg) abdominal injection to anesthesia before the operation, use the insision at left iumbar-back part which parallel the spine ,passivityly disconnect the greater psoas muscle and the fat which adhere with it ,get into the posteria abdominal membrane space and expose the left kindey, press and fix the kidney and the renal pedicle, raise the greater psoas muscle and expose the the abdominal aorta, disconnect the left renal artery at the part that renal pedicle is near the the abdominal aorta, use the no-injury bulldog clamp to block the left renal artery, then count the time,to observe colour of the kindey from dark red to dark black.Block the left renal artery for 45 minutes,removing the bulldog clamp,recovering the provision of the artery, observe colour of the kidney to turn dark black to red in a short time(imply the kidney has recovered artery supplying).3.To draw the tissue from specimen remove the kidney of all the rats , left intersect the kidney at the middle of the renal pedicle ,put the superior of the kidney into the -77℃fridge,prepare to do the tissue hemogenate.Fix the inferior with 10% formaldehyde,prepare to do the pathelogical section. 4.Results detect (1) activity and contents of the SOD,MDA in the left kidney(2) the morphoragy of the pathelogical section stained by HE under the light microscope.Results: 1.The change of the acticity of the SOD in left kidney the compare difference between B,C and D has no statistics significance, the compare difference between A and B has no statistics significance,but has the tatistics significance between C, the compare difference between B and C has the statistics significance.2. The change of content of MDA in the left kidney content of the MDA in kidney tissue of group A,B,C and D has the tendency of graduatedly increase and all higher than group E, the compare difference between A,B,C and E has no statistics significance, the compare difference between A,B,C,E and D has the statistics significance, the compare difference among A,B and C has no statistics significance.3. The change of morphology of the pathelogical section stained by HE stained under the light microscope. In the grou D, the glomcrulus and nephric tubule have no abnormal change of groug E by HE stain. The glomcrulus has no abnormal change,but in the proximate tubule,the epithet- lial cells lamellarly necrosis, the tube cavity dilates and can see the fragments of defluxion cells and protein-shape cast, pycnosis, fragmenta- tion of the epithelial cells, kytoplasm vacuole degenerate and necrosis,the space among cells increase,the renal matrix congestion , edema and infiltrated by inflammatory cells. In the group A ,the glomcrulus has no abnormal change,but in the proximate tubule, the tube cavity dilates and can see a few fragments of defluxion cells but no protein-shape cast, swell and kytoplasm vacuole degenerate of the epithelial cells, the space among cells increase,the renal matrix congestion , edema and infiltrated by a few inflammatory cells. The damage range and degree of grougs B and C are less than group D,but worse than group A.Results:1.This experiment can successfully establish the animal model which cause the ischemic reperfusion injury of one kidney and conserve the opposite side kidney ,make sure the good condition of the rats 24 hours after the operation,finish the index detect which we need.2.The high effective antioxidation drug tea polyphenols and vit.C through intra-veins injection can reduce the damage of renal function caused by ischemic reperfusion injury,especially for the group of high dose tea polyphenols(TP 100mg/kg),the mechanism is inducing the endogenous protect of the organism,raising the activity of the SOD to clear the oxyradical direct or indirect,lessening the lipid peroxidize to protect the kidney .3.This study provide experimental basement for the exploit and use of TP.