Coda mouse rat tail cuff system

Serum insulin concentrations were determined with the rat insulin Elisa kit 90010 (Crystal Chemical Co. USA). The blood glucose concentrations were evaluated using an Accu-Check Active auto-analyzer (Roche, Germany). Total cholesterol and triglyceride levels were determined in blood samples after 12 h fasting (5 (link)) with the Accutrend Plus auto-analyzer (Roche). According to the manufacturer, this instrument has an intra-assay precision of 3.7% for total cholesterol and 3.4% for triglycerides. Using controls, we calibrated the intra-assay precision as 5% for total cholesterol and 2.4% for triglycerides. Blood pressure was evaluated with the CODA^® mouse rat tail-cuff system, a noninvasive small animal blood pressure monitoring system (Kent Scientific Corp., USA).

Sprague-Dawley rats were randomly divided into 4 groups: male kidney ischemia-reperfusion, male control, female kidney ischemia-reperfusion and female control. Each group consisted of 6 rats. Kidney ischemia was induced in male and female rats (250–300 g) by clamping the left renal pedicle with a non-traumatic vascular clamp for 45 min, as described in our previous studies [25 (link),26 (link),27 (link),28 (link)]. At the end of ischemia, the clamp was removed to allow blood flow to the left kidney (reperfusion) and right nephrectomy was performed. As a control (sham-operated), male and female rats were subjected to the same surgical procedure but without kidney ischemia. The heart rate was measured in rats using the CODA™ mouse rat tail-cuff system (Kent Scientific corporation, Torrington, CT, USA). Rats were sacrificed 24 h after the surgery. All procedures were performed in accordance with the Guide to the Care and Use of Experimental Animals published by the Canadian Council on Animal Care and approved by the University of Manitoba Protocol Management and Review Committee. Blood was collected from the abdominal aorta and plasma was prepared by centrifugation at 3000× g for 20 min at 4 °C. Plasma and heart were stored at −80 °C until analysis.