Figure 2.

GLP-1 increases muscle ¹²⁵I-insulin uptake. Each rat received a 90-min euglycemic insulin clamp (3 mU/kg/min) with or without simultaneous GLP-1 infusion (30 pmol/kg/min) for the last 30 min. A bolus intravenous injection of ¹²⁵I-insulin (1.5 µCi) was given 5 min before the end of insulin ± GLP-1 infusions. Blood and skeletal muscle were collected for determination of intact ¹²⁵I-insulin. A: Study protocol. B: Fraction of intact ¹²⁵I-insulin in blood and muscle. C: Muscle insulin uptake. n = 5 each. Compared with insulin alone, *P < 0.05.