Binding to its receptor activates G proteins and stimulates adenylate cyclase in pituitary cells (By similarity). Promotes neuron projection development through the RAPGEF2/Rap1/B-Raf/ERK pathway (By similarity). In chromaffin cells, induces long-lasting increase of intracellular calcium concentrations and neuroendocrine secretion (By similarity). Involved in the control of glucose homeostasis, induces insulin secretion by pancreatic beta cells (By similarity). Interacts with ADCYAP1R1 (via N-terminal extracellular domain). Belongs to the glucagon family.