Ghrelin is mainly released from which part of the body?

Ghrelin is primarily produced and secreted by the stomach, particularly from specialized cells known as endocrine cells in the gastric mucosa. This hormone plays a crucial role in regulating appetite and energy balance by stimulating hunger sensations and promoting food intake. When the stomach is empty, ghrelin levels rise, signaling the brain to increase appetite and food-seeking behavior. Therefore, the correct answer highlights the stomach as the main source of ghrelin production.

While the liver, pituitary gland, and pancreas each have important functions in metabolism and hormone regulation, they do not produce ghrelin. The liver is involved in glucose metabolism, the pituitary gland secretes various hormones that regulate numerous bodily functions but is not a source of ghrelin, and the pancreas plays a key role in insulin production and regulating blood sugar levels. Understanding the specific origin of hormones like ghrelin helps clarify their functions in the body's complex systems of appetite and energy regulation.