Glucagon, secreted in the A cells of the islets of Langherans, plays a key role in glucose metabolism and homeostasis. Proglucagon is processed in glucagon, GLP-1, GLP-2, glicentin and oxyntomodulin depending on tissue. Glucagon is used to treat severe hypoglycemia in insulin-dependent diabetics under the names Glucagon (Eli Lilly) and GlucaGen or Glucagon Novo Nordisk (Novo Nordisk).Human: H-His-Ser-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Lys-Tyr-Leu-Asp-Ser-Arg-Arg-Ala-Gln-Asp-Phe-Val-Gln-Trp-Leu-Met-Asn-Thr-OH or H-HSQGTFTSDYSKYLDSRRAQDFVQWLMNT-OH