[Mechanism and effect of cyclooxygenase-2 inhibitor meloxicam on the protection of diabetic nephropathy in rats].

OBJECTIVE

To investigate the renal protective effect of specfic cyclooxygenase 2 inhibitor meloxicam on the renal of diabetic nephropathy rats.

METHODS

Twenty-eight Sprague-Dawley (SD) rats with diabetic nephropathy by intraperitoneal injection of streptozotocin were randomly divided into 2 groups: diabetic nephropathy without any treatment (Group D,n = 14), and diabetic nephropathy treated with meloxicam. (Group M,n = 14). Another 12 normal rats were divided into normal control (Group N, n=12), and then Group M began to receive a blocker of cyclooxygenase 2 inhibitor, meloxicam [2 mg/(kg x d)]. Six weeks after the induction of DN, 24 h urine and blood samples were collected and kept at -70 degrees C. Then rats were killed. Their kidneys were removed and longitudinal halved. One half was placed and stored in fixation solution until COX-2 immunohistochemistry was determined.

RESULTS

The creatinine clearance rate, uria protein, and the expression of COX-2 in renal and urinary TXB2 in diabetic rats were significantly higher than in Group N. Meloxicam decreased uria protein or creatinine clearance rate significantly (P < 0.01). Immunohistochemical analysis revealed the decreased expression of COX-2 in the renal of Group M by the meloxicam treatment.

CONCLUSION

Meloxicam can protect diabetic kidney, somehow through deceasing the renal expression of COX-2.