What is the primary function of gastrin?

The primary function of gastrin is to stimulate acid secretion and promote the growth of parietal cells in the stomach. Gastrin, a peptide hormone produced by G cells in the gastric mucosa, is released in response to food in the stomach. When released, it binds to specific receptors on the parietal cells, leading to an increase in the secretion of gastric acid (hydrochloric acid). This acid is essential for digestion, as it helps break down food and activates digestive enzymes.

Additionally, gastrin plays a role in promoting the proliferation of parietal cells, ensuring that there are enough of these cells to maintain adequate acid production as needed, especially after meals. The response initiated by gastrin is crucial for effective digestion and maintaining the proper acidity of the stomach, which is vital for the digestive process.

The other options refer to functions that are undertaken by different hormones or biological processes not directly linked to gastrin, thereby clarifying the unique role of gastrin in the digestive system.