The application of angiotensin converting enzyme inhibitor administration in renal transplant recipients

Objective To observe the protective role of enalapril as a specific angiotensin converting enzyme inhibitor on allograft in renal transplant recipients. Methods From Jan 2000 to Jun 2001,22 cases of renal transplant recipients with normal renal function and urine TGF- β1 concentration being higher than 250.0 pg/mg Cr（ group A） underwent therapy with angiotensin converting enzyme inhibitor （enalapril） one year after surgery. Enalapril was administered at a close of 50 mg/d for the patients in group A for at least one year. Twenty - three recipients who never received angiotensin converting enzyme inhibitor in the same condition were studied as Group B. The adverse reactions of enalapril were investigated in group A and the expression of TGF -β1 mRNA in renal grafts were compared between before and 1 year after enalapril therapy. At the end of 3 - year study period, the renal function, the decrement of creatinine clearance rate（Ccr） and the concentration of TGF- β1 in blood and urine were compared between the two groups respectively. Results The Ccr decreased faster in group B than in group A. During three years study period, the decrements of Ccr were （5.1± 4.6 ） and （ 13.7±9.5 ） （ml/min） in group A and group B respectively, and there were 2 cases and 9 eases with chronic allograft nephropathy （ CAN ） respectively. The decrement of Ccr and the number of CAN cases were significant difference between group A and group B（all P 〈0. 05）. The concentrations of urine TGF -β1 were （325.3 ±46. 3） and （507.7 ±53.1 ） （pg/mg. Cr） in group A and group B respectively 3 years after treatment with enalapril, with significant difference（ P 〈0. 01 ）. There was not significant difference in the concentration of blood TGF-β1 between the two groups. After treatment with enalapril for one year, the expression of TGF - β1 mRNA in Group A decreased from （ 1.57 ±0. 31 ） to （0. 94 ±0. 27）. No adverse reaction happened in the patients treated with enalaprd Conclusions There is a protective role of enalapril as a specific angiotensin converting enzyme inhibitor on allograft in renal transplant recipients, which is related with the decrease of the TGF - β1 in the kidney. Key words: Kidney transplantation ;  Nephropathy ;  TGF - β1;  Enalapril