Caffeic acid phenethyl ester effects in the kidney during ischemia and reperfusion in rats anesthetized with isoflurane.

BACKGROUND: The purpose of this investigation was to examine the effect of caffeic acid phenethyl ester (CAPE) in renal ischemia/reperfusion injury in rats anesthetized with isoflurane (iso). METHODS: We randomly assigned 26 male Wistar rats anesthetized with isoflurane, intubated and mechanically ventilated to 3 groups: G1 (controls; n = 8), G2 (CAPE; n = 10), and G3 (ethanol; n = 8). Mean arterial pressure was monitored for anesthetic control. Intraperitoneal CAPE (G2) or ethanol (G3) injections were administered 40 minutes before left renal ischemia. All animals underwent right nephrectomy and the left kidney was submitted to ischemia for 25 minutes. Serum creatinine (cr) values were determined at the beginning (M1), end (M2), and 24 hours after the experiment (M3) upon intracardiac blood samples. The left kidney was removed for histologic analysis, using a scale for tubular necrosis (0-5, injury maximum). Statistical analysis was applied to serum creatinine and histological score injury considering statistical differences to be significant when P < .05. RESULTS: The cr values in the CAPE were significantly higher at M2 (0.8 mg/mL; P = .0012) and M3 (3.7 mg/mL; P = .0014) than the control (0.5 and 0.9 mg/mL) or G3 (0.6 and 1.0 mg/mL), respectively. Histologic examination showed the CAPE group to display more pericapsular tubular necrosis (3.0 [2.0; 3.0]) than the G1 group (2.0 [1.0; 2.0]) or G3 group (1.5 [1.0; 2.0]; P < .001). The CAPE group displayed more medullary tubular necrosis (2.0 [2.0; 3.0] than G1 (2.0 [1.0; 2.0] or G3 (1.0 [0.0; 2.0]; P < .001). CONCLUSION: CAPE promoted greater functional and anatomic renal injury when rats were anesthetized with iso than control or ethanol groups, as demonstrated by histologic analysis and serum values.