Quizbowl science/Biology/Epinephrine

Epinephrine or adrenaline is an amino acid derivative hormone (polar). It is released from the adrenal medulla. Functions Acts on liver cells to increase blood glucose by: increasing glycogen breakdown and increasing gluconeogenesis. Acts on muscle cells to make ATP by increasing glycogen breakdown increasing glycolysis increasing beta-oxidation (breaking down fatty acids to get energy) Basically, the liver makes glucose, and the muscle breaks down that glucose, so ATP is available for fight-flight. Mechanism Epinephrine binds a G-protein coupled receptor, activating adenylate cyclase, which produces cAMP from ATP. This causes protein kinase A to become more active. PKA phosphorylates: makes glycogen synthase less active activates phosphorylase kinase -- makes glycogen phosphorylase more active (involved in glycogen breakdown -- glycogenolysis)