Objective To explore the effect of ACE-inhibitor perindopril on the expression of scavenger receptor A (SR-A) gene in the kidney of diabetic rats.Methods Diabetes were induced in male Sprague-Dawley rats by peritoneal injection with streptozotocin (60mg/kg).The rats were then random di vided into normal control group, diabetes group and ACEI treatment group [4mg/(kg·d) for 24 weeks].Blood glucose concentration and 24h urinary albumin excretion were determined.The renal morphological change was observed.Immunohistochemistry was used to analyze CD68 positive macrophages,and the Mrna of SR-A in renal tissue was detected by quantitative real-time PCR.Results Compared with normal control group,blood glucose concentration,24h urinary albumin excretion and the number of CD68 positive macrophages were significantly increased [(5.3 ± 0.6) mmol/L vs (26.7 ± 3.3) mmol/L;(2.7 ± 1.3) mg/24h vs (26.7 ± 1.8)mg/24h;(0.77 ±0.24)/gcs vs (2.55 ±0.46)/gcs;(6.13 ±0.50)/HPF vs (11.9 ±2.12)/HPF;P ＜0.05],and the expression of SR-A Mrna were significantly up-regulated in diabetes group [ (5.6 ± 1.2 vs 1.5 ±0.2),P ＜0.05].After intervention with ACE-inhibitor,the up-regulations of the above mentioned parameters,except blood glucose concentration,were all significantly inhibited [ (3.6 ±1.4)mg/24h;(1.03±0.37)/gcs;(8.28±1.19)/HPF;3.4±0.7;P ＜0.05].Conclusion ACE-inhibitor might have renoprotective effects of diabetic nephropathy,it probably was associated with inhibiting the expression of SR-A gene.