Rats were weighed, anesthetized with isoflurane, and femoral arterial catheters implanted for blood collection and determination of blood glucose (
Accu-Check Compact, Roche Diagnostics, Indianapolis, IN) and lipid profile (Cardio-Check PA analyzer, QAS, Orlando, FL). Additional blood was collected in tubes containing EDTA and plasma obtained by centrifugation. Plasma levels of specific proteins were determined using commercial
ELISA kits for insulin (Cayman Chemical, Ann Arbor, MI), tumor necrosis factor-α (
TNFα) (Thermo Scientific, Waltham, MA), and oxidized low-density lipoprotein (oxLDL) (Mercodia, Winston Salem, NC). Circulating levels of amino acids were quantified by ion exchange chromatography (Molecular Genetics Laboratory at Baylor College of Medicine, Houston, TX). Global arginine bioavailability, which is a more sensitive indicator of disturbances in arginine metabolism than levels of individual amino acids, was calculated as the ratio of plasma arginine to the sum of plasma ornithine plus citrulline.
13 (link),14 (link) Following blood collection, animals were heparinized (1000U/kg, iv) and the thoracic aorta and gracilis anticus muscles removed.
Johnson F.K., Peyton K.J., Liu X.M., Azam M.A., Shebib A.R., Johnson R.A, & Durante W. (2014). ARGINASE PROMOTES ENDOTHELIAL DYSFUNCTION AND HYPERTENSION IN OBESE RATS. Obesity (Silver Spring, Md.), 23(2), 383-390.