Comparative Study About The Renal Protective Effect Of Aliskiren, Irbesartan, Alodipine On Anti-inflammation In Rats With Atherosclerosis And Renal Artery Stenosis

Background and Objective：With the aging of population and the influence of unhealthylifestyles，atherosclerosis renal artery stenosis has become theleading cause of renal artery obstruction(about71.9%)，eventually leading to end stage renal disease(ESRD).Studieshave found the degree of renal artery stenosis caused byatherosclerosis and kidney damage severity were not completelyparallel，speculating the chronic renal injury may be caused byother factors other than vascular stenosis， Inflammation andplaque stability may be an important mechanism of downstreamkidney damage progress. Fractalkine is a chemotactic factorwith the activity of adhension，involved in white blood cellsmigration and activation.FKN released by endothelial cellscombined with its receptor CX3CR1expressed on natural killercells （NK） cells， mononuclear cells， lymphocytes， canaccelerate the formation of atherosclerosis and influence theatherosclerotic plaque stability.In addition，FKN expressed inprimary and secondary renal disease and other inflammation disease and played an important role of promoting renalinflammatory response by mediating chemotaxis and adhesionof inflammatory cells.However，there is no report on correlationbetween atherosclerosis renal artery stenosis inflammatorykidney injury damage and Fractalkine. antihypertensive drugscan reduce arterial pressure，and have the effect of reducingdarget organ damage.However， the application ofantihypertensive drugs in atherosclerotic renal artery stenosis isstill controversial. Whether antihypertensive drugs can reduceinflammatory renal injury by intervening FKN/CX3CR1expression deserve further study.Therefore we use differentoperation (one kidney one clip，two kidney one clip) and highfat feeding to establish the animal model of atherosclerosis andrenal artery stenosis.By measuring the change of renal functionand plasma rennin activity(PRA)，observing and measuring thedistribution and volume change of inflammatory chemokineFKN/CX3CR1in narrow side kidney，we explore the correlationbetween FKN/CX3CR1and inflammatory renal damage causedby atherosclerosis，and the intervention effect of Aliskiren，irbesartan，Alodipine.The propose is to provide a theoreticalbasis for the rational treatment of renal damage caused byatherosclerotic renal artery stenosis. Method：1.Animal model：78male SD rats were randomly divided intoone kidney，one clip(1K1C)group，two kidney one clip(2K1C)and control group，1K1C and2K1C group were renal arterystenosis using parallel and acupuncture needles method，andonly exposed the left renal artery in control group.The rats wereinjected VitD30.05million IU/kg and high fatdiet(10%lard+5%sugar+2%cholesterol and0.5%cholic acid) toestablish the model of renal artery stenosis and AS in10weeks.2.Comparative study about the effect of Aliskiren，irbesartan，Alodipine on kidney inflammation injury in rats withatherosclerosis and renal artery stenosis：After10weeks offeeding，the control group and the1K1C group，2K1C groupwere randomly grouped and given interventions：salinegroup(0.9%NS2ml/d)，aliskiren group(50mg/kg.d)，irbesartangroup(100mg/kg.d) and amlodipine besylate group(6mg/kg.d)，intervention time is4weeks.After that the following steps weregiven：(1) Blood collection from heart，then detected the serumcreatinine，plasma rennin radioimmunoassay acitivity(PRA) byautomatic biochemical analyzer.(2) taken the narrow side ofkidney in SD rats，PAS staining was taken in one part and theother for-70℃cold storage.(3) using immunohistochemistry to detect the expression of Fractalkine，CX3CR1in kidney ofexperimental rats，and PBS instead of primary antibody asnegative control，the brown area is positive results，usingImage-pro plus6.0software analysis the Image which werecollected，and comparing the average optical density values ofeach group.(4)using RT-PCR to detect the expression ofFractalkine mRNA，CX3CR1mRNA in kidney of experimentalrats，take cryopreservation kidney tissue for RNA extraction，reverse transcription，PCR and electrophoresis，using Quangtityone software analysis of gray values about the target band andthe internal reference band， comparing the change of theexpression of Fractalkine mRNA，CX3CR1mRNA in kidney ofexperimental rats.Results：1. The effect of antihypertensive drugs on blood pressure:In thesame mode of operation，compared with the saline group，theintervention group blood pressure decreased, the difference wassignificant (P <0.05), but the antihypertensive effect of all kindsof drugs were not significant.2. The effect of antihypertensive drugs on renal function:Therats were fed14weeks later，in the same mode of operation，compared with the saline group，2K1C aliskiren group and 2K1C irbesartan group creatinine elevated levels weresignificantly decreased， the difference was significant (P<0.05)，among them, the aliskiren group decreased more thanthe irbesartan group (P <0.05). Aliskiren did not cause elevatedcreatinine in1K1C group， the1K1C irbesartan groupcreatinine significantly increased. The difference between thealiskiren group and the amlodipine group group also wassignificant (P <0.05).3.Regulation of antihypertensive drugs on plasma PRA secretion:compared with sham operated saline group，2K1C saline groupPRA significantly increased (P <0.05)，In the same mode ofoperation，compared with sham operated saline group，thealiskiren group PRA decreased significantly (P <0.05),However，2K1C,1K1C amlodipine group PRA weresignificantly increased (P <0.05)，Bwteen the aliskiren groupand the amlodipine group，the differences were significant (P<0.05)，but between the irbesartan group and the amlodipinegroup, the difference was not significant (P>0.05).4. The intervention effect of antihypertensive drugs on FKN andCX3CR1expression:compared with the sham saline group，the1K1C,2K1C saline group Fractalkine and CX3CR1expressionin renal tubules was significantly increased (P <0.05). In the same mode of operation，compared with normal saline group，aliskiren, irbesartan group, amlodipine group Fractalkine andCX3CR1expression was decreased (P <0.05)，aliskiren groupis especially clear. Between2K1C irbesartan group and the2K1C amlodipine group the difference is significant (P <0.05)，compared with1K1C aliskiren group，2K1C aliskiren groupFractalkine and CX3CR1expression decreased moresignificantly (P <0.05).5.Detection of Fractalkine mRNA，CX3CR1mRNA in kidneyof experimental rats：Compared with the saline group，thealiskiren group and the irbesartan group Fractalkine andCX3CR1expression were significantly decreased (P <0.05),while Between amlodipine1K1C and amlodipine2K1C groupthe difference was not significant (P>0.05), consistent with theresults of immunohistochemistry.Conclusion:1. Inflammation factors may involved in the atherosclerosis withrenal artery stenosis kidney damage process.2. The antihypertensive effect weresimilarly，but the aliskirensignificantly reduce the level of PRA in renal artery stenosis ofrats.3. Aliskiren may protect renal by reducing the expression of FKN/CX3CR1，it was superior in anti-inflammatory renal injurycaused by atherosclerosis and renal artery stenosis.