Pancrease is a mixed gland because it has both endocrine part (secretes hormone) and exocrine part (secretes pancreatic juice). Secretin is a hormone secreted from intestine, it stimulate secretion of pancreatic juice. Renin is a hormone secreted from kidney, which regulates erythropoesis (ie, formation of RBC) gastrin is a hormone secreted from stomach which stimulate secretion of gastric juice.