Insulin Sensitivity Testing (IST)
Insulin resistance is involved in the pathogenesis of obesity, diabetes, and a variety of cardiovascular diseases. This test can be used to identify whether a mouse is insulin resistant by measuring the rate at which glucose is metabolized.
Mice are fasted overnight (~14 hours), then injected via the intraperitoneal cavity, or if obese, via the sub-cutaneous sub-scapular region with Humulin R insulin in sterile PBS at a dose of 1.0 units insulin per kilogram body weight. Plasma glucose is monitored prior to glucose injection and at 30 minutes after injection. The percentage decrease in glucose between these time points is then calculated as follows: % glucose disposed = [(glucoset=0 glucoset=30)/glucose t=0] x 100