257-OR: Short-Term Hyperglucagonemia Induces Adipose Tissue Insulin Resistance and Inflammation In Vivo

Although the effect of glucagon on glucose metabolism has been well characterized, its effect on adipose tissue and lipid metabolism in humans in vivo has been poorly studied with controversial results. We examined the effect of short-term hyperglucagonemia on adipocyte metabolism in 8 healthy normal glucose tolerant subjects (5M/3F, age=35±5, BMI = 24±1) who received a 12-hour (6PM to 6AM) glucagon infusion (6ng/kg/min) with 14C-glycerol infusion; subcutaneous abdominal adipose tissue biopsy was obtained at 6AM. 8 weeks later subjects returned for a repeat study with 12-hour infusion of normal saline. Plasma glucagon increased from 57±3 to 219±21 pg/ml within one hour and remained elevated throughout the study. Glycerol turnover rate (5.1±0.6 vs. 3.8±0.6 µmol/kg•min, p