They were kept under standard conditions (light/dark cycle: 12 h; humidity: 25-35%; and temperature: 22-28˚C) with standard food and water ad libitum. All the animal procedures were approved by the Institutional Committee for Care and Use of Animals. Materials Streptozotocin was obtained from Teva Parenteral Medicine
Inc. (Irvine, CA, USA). Nicotinamide (NA) was purchased from Sigma-Aldrich Chemical Co. (Steinheim, Germany). Inhibitors,research,lifescience,medical Streptozotocin and NA were dissolved in sodium chloride (0.9%). Ketamine and Xylazine were obtained from Alfasan (Woerden, Holland). Triphenyltetrazolium Chloride (TTC) was obtained from Sigma-Aldrich Chemical Co. (Steinheim, Germany). Kits for the measurement of coronary artery effluent creatine kinase (CK-MB) were obtained from Pars Azmoon Company (Pars Azmoon, Tehran, Iran). Experimental Design The animals (n=35) were randomly allocated to five groups, including a type 2 diabetes control group (n=7), a type 2 diabetes group (n=7), a click here Renovascular Inhibitors,research,lifescience,medical hypertensive (HTN) group (n=7), a sham-operated group (Sham) (n=7) as a control for the renovascular hypertensive group, and a simultaneous type 2 diabetes (n=7) and renovascular hypertensive (HTN) group Inhibitors,research,lifescience,medical (n=7). Experimental Protocol Induction of Diabetes and Renovascular Hypertension Type 2 diabetes was induced by injecting the animals with single intraperitoneal administrations of NA (110 mg/kg) 15 min before single intraperitoneal administrations
of STZ (60 mg/kg).11 Seven days later, the animals’ blood glucose was determined using a Glucometer (Accu-Chek® Inhibitors,research,lifescience,medical active, Mannheim, Germany), and those with fasting blood glucose (FBG) levels higher than 126 mg/dl were taken as having type 2 diabetes.12
Six weeks after the injection of NA and STZ or normal saline, the animals were subjected to sham operation Inhibitors,research,lifescience,medical or placement of solid Plexiglas clips on the left renal arteries to induce two-kidney, one-clip renovascular hypertension as was described previously.13 Briefly, under Ketamine (60 mg/kg) and Xylazine (8 mg/kg) anaesthesia, incisions were made in the left flanks, and the left renal arteries and veins were exposed. The arteries were gently dissected from the veins, and solid Plexiglas clips (internal diameter=0.20-0.22 Bumetanide mm) were placed on the left renal arteries. The abdominal wall and skin incisions were then sutured using absorbable (catgut-3/0) and non-absorbable (silk-3/0) suture materials, respectively. The sham-operated animals were subjected to the same procedure, but no clip was placed on the left renal arteries.13 Four weeks after the sham-operation or induction of renovascular hypertension, the animals’ systolic blood pressure (SBP) and heart rate (HR) were measured using the noninvasive tail-cuff (Chart 5.0 software, PowerLab 4/30, ADInstruments Inc., MA, Sydney, Australia) method. Three consecutive measurements of blood pressure, which had a difference of less than 5 mm Hg, were considered valid.