Effect of NA on GSIS in 18- to 24-h–fasted (A) or fed (B) rats. At 0 min, the rats received an intravenous bolus of glucose to raise the plasma glucose concentration to ∼14 mmol/l
at +5 min. Thereafter, the plasma glucose concentration was clamped at ∼11 mmol/l. In addition, they received vehicle (○),
NA (□), or NA plus Intralipid (IL) and heparin (HEP) (▵) from −60 min onward (reproduced from ref. 70).