A study nurse and/or doctor will be by the bedside throughout the clamp and will be monitoring the participant's blood glucose every 30 minutes after the onset of the clamp and every 10 minutes after administration of glucagon (if clinically indicated, sampling may be more frequent) to ensure participants do not develop hypo/hyperglycemia. Blood samples will be analysed with a glucometer for instant blood glucose readings. If intranasal glucagon reduces endogenous glucose production, a reduction in plasma glucose is likely. 20% dextrose will be administered if necessary to maintain euglycemia At 9 am (+120 minutes) intranasal placebo or glucagon will be administered. The glucagon (Eli Lily, Canada) and placebo (diluent) will be transferred to a metered nasal device (Pharmasystems, Markham, Ontario UPC: 063636 802721, Item 10271) immediately prior to use. This device dispenses 0.1ml (0.1mg) per puff. A maximum of 15 X0.1 ml puffs/vials (7 in 1 nostril and 8 in the other nostril) will be administered at rate of 2 (one in each nostril) every 60 seconds. This dose may be titrated down if necessary to reduce peripheral spillover.