Buprenorphine given after surgery does not alter renal ischemia/reperfusion injury

Background and Purpose: Potential drugs for human acute renal failure are o ften tested in an animal model of renal ischemia/reperfusion injury. Analge sics are often not given after surgery because of concerns that they would alter renal function. Therefore, we tested whether postoperative analgesia would alter animal health or affect the degree of renal injury. Methods: Mice were subjected to either 32 or 37 minutes of renal ischemia, given two or six doses of buprenorphine or vehicle at 12-hour intervals, an d followed for 72 hours. In some animals, we measured body temperature and physical activity by use of telemetry. Results: Animals treated with buprenorphine recovered more rapidly from sur gery based on postoperative activity, and had a small but not significant t endency for faster restoration of normal body temperature. Animals treated with buprenorphine had less weight loss after 37 minutes of ischemia, Bupre norphine given after surgery did not influence the degree of renal injury a fter ischemia/reperfusion. Conclusions: Buprenorphine should be given after renal ischemia-reperfusion surgery because administration of the proper analgesic improved animal hea lth without interfering with the renal ischemia/reperfusion model. Analgesi c treatment at the time of the operation and 12 hours after was sufficient. Buprenorphine may reduce the post-surgical stress response, and thus poten tially improve the specificity of testing for drugs that reduce or treat re nal injury.