 Meal challenge test:- In order to assess the changes induced by liraglutide, a meal challenge will be carried out prior to and following liraglutide day 0 and day 84. 910 Calorie High fat High carbohydrate meal as in several of our previous papers. Acetaminophen 1000 mg for body weight 70 kg or 1500 mg for body weight 70 kg will be ingested at the beginning of the meal, and the blood levels of acetaminophen will be determined at intervals for assessment of the rate of gastric emptying. Bolus Insulin will be injected immediately before the meal based on the insulin carbohydrate ratio and correction factor for each individual subject. Liraglutide will be injected only on day 84 45 min prior to the meal. Sequential blood samples will be obtained at 0, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240 and 300 min. Samples at 15, 30, 45, 90, 150 and 210 min will be 5 ml while those at 0, 60, 120, 180, 240 and 300 min will be 30 ml total volume210 ml. Blood will be collected from an indwelling intravenous canula in a superficial forearm vein. 