PRL and Hypoglycemia: The insulin challenge dose was 12 U/kg, which was higher than the 3 U/kg dose used in the PRL-2903 experiment, selected with the intent to induce level 2 hypoglycemia (<3.0 mmol/L) in the control group, whereas level 1 hypoglycemia (3.5 mmol/L blood glucose) was achieved in the PRL-2903 study.