Nine healthy men completed 3 study days : i ) saline control ( CTR ) , ii ) hyperinsulinemic euglycemia ( HE ) ( bolus insulin 0.1 IE/kg i.v. and glucose 20 % i.v. for 105min , plasma glucose 5mmol/l ) , and iii ) hyperinsulinemic hypoglycemia ( HH ) ( bolus insulin 0.1 IE/kg i.v. ) .