Recombinant Human Gastrin protein

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

Gastrin sometimes referred to as gastrin peptide is a hormone consisting of 34 amino acids with a molecular mass of approximately 3.8 kDa. This protein is mainly expressed in the G cells of the stomach lining specifically the antrum but also found in the duodenum and pancreas. Gastrin operates by stimulating the secretion of gastric acid from parietal cells in the stomach playing an important role in the digestive process. The presence of gastrin can be detected through various methods like gastrin stain and antibodies such as anti-gastrin are often used for this purpose.

Biological function summary

Gastrin impacts digestion and is an important promoter of gastric acid secretion and mucosal growth. Gastrin does not assemble into larger protein complexes functioning instead as an independent peptide hormone. It exerts its effects by binding to the cholecystokinin B receptor (CCK-B) on target cells leading to increased intracellular calcium levels and activation of protein kinases. The interaction initiates a cascade of events facilitating digestion by optimizing the stomach's environment.

Pathways

Gastrin has a significant role in the gastrointestinal (GI) pathway where it activates the secretion of hydrochloric acid. It also influences the phosphoinositide pathway through its relationship with G-proteins. The hormonal action of gastrin involves several other proteins like somatostatin which serves as an inhibitory counterpart and histamine that works synergistically by promoting further acid secretion through different receptors.

Physicians often study gastrin in relation to conditions like Zollinger-Ellison syndrome and peptic ulcers. Zollinger-Ellison syndrome leads to excessive production of gastrin causing severe ulcerations and gastric acid secretions. Concurrently elevated gastrin levels sometimes associate with tumors like gastrinomas. The interplay between gastrin and H. pylori infection is pivotal for peptic ulcer development where bacteria-induced inflammation could alter gastrin's normal regulatory functions of acid secretion.