Abstract: To observe the protective effect of D-Amyloid precursor protein 63～73 named APP-11 mer peptide from diabetic nephropathy, the peptide was administrated by subcutaneous injection for 4 weeks to diabetic rats induced by streptozotocine. The concentration of glucose and its regulated hormones, urea nitrogen and creatinine in the blood were determined at the end of experiment for 3 groups, hade normal group, diabetic group and diabetic group treated by APP-11 mer peptide. The difference of excretion of uric albumin in the above mentioned 3 groups was also detected, and the kidney cortex was taken for ultrastructure research. The results showed that diabetic rats had much more excretion of uric albumin than that of normal rats and diabetic rats treated by APP-11 mer peptide. Although no effect was observed on the concentration of blood sugar, insulin, glucagon and creatinine, urea nitrogen was decreased in the rats treated by APP-11 mer peptide. On the ultrastructure, thickness of basic membrane and enlargement of the endothelial hole of glomerulus in diabetic kidney were found, but APP-11 mel peptide could improve their changes significantly. The results showed that APP-11 mer peptide can improve the diabetic nephropathy, although no one knows the mechanism.

Key words: APP-11 peptide, diabetic rats, nephropathy