What type of substance is secreted by non-beta cell tumors in Zollinger-Ellison syndrome?

In Zollinger-Ellison syndrome, non-beta cell tumors, specifically gastrin-secreting tumors known as gastrinomas, lead to excessive production of gastrin. Gastrin is a hormone that stimulates the secretion of gastric acid, thereby facilitating digestion and altering gastrointestinal motility.

The presence of the gastrinomas results in increased levels of gastrin in the bloodstream, causing symptoms associated with excessive gastric acid production, such as recurrent peptic ulcers and abdominal pain. The fact that these tumors arise from non-beta cells is crucial; they do not originate from the pancreatic beta cells that produce insulin, but rather from cells that can produce hormones related to gastric function.

In summary, the secreted substance in Zollinger-Ellison syndrome is a gastrin-like substance, which is responsible for the hallmark symptoms of the disorder. This emphasizes the role of gastrin in gastrointestinal physiology, particularly in relation to acid secretion and ulcer development.