Glucagon activates lipolysis and signals for the release of free fatty acids from fat cells, especially during fasting.

“well of course glucagon helps to activate more lipolysis and thus the release of the free fatty acids from adipocytes so your adipocytes are your fat cells and effectively what's happening on a constant endless basis is actually they're being energies being parked in them and then over time they're being released they're kind of like a large number of mini gas tanks all around your body and for the most part they're either in one of two states for the most part they're either being filled so insulin is higher it's now time to shuttle energy into them in which case things are coming in or it's time to release which is typically during the fasted state and they're slowly slowly releasing non-esterified fatty acids as they're known in the literature and glucagon is part of the signal to say go ahead and release”