Sources, Regulation, and Functions of Gastrointestinal (GIT) Hormones

Overview of GIT Hormones

Gastrointestinal (GIT) hormones play a crucial role in the regulation of digestive processes and metabolic activities. These hormones are secreted by specialized cells in the gastrointestinal tract and are responsible for coordinating digestion, absorption, and motility.

Sources of GIT Hormones

• Gastrin: Secreted by G cells in the stomach lining.
• Cholecystokinin (CCK): Produced by the small intestine.
• Secretin: Released from S cells in the duodenum.
• Ghrelin: Mainly secreted by the stomach.
• Motilin: Produced in the small intestine.

Regulation of GIT Hormones

GIT hormones are regulated through complex feedback mechanisms involving neural, endocrine, and paracrine signaling pathways. Factors such as food intake, nutrient composition, and neural stimuli play a pivotal role in modulating their secretion.

Functions of Key GIT Hormones

• Gastrin: Stimulates gastric acid secretion and promotes mucosal growth.
• Cholecystokinin (CCK): Facilitates bile release and pancreatic enzyme secretion.
• Secretin: Regulates pH by stimulating bicarbonate secretion.
• Ghrelin: Influences appetite regulation and energy balance.
• Motilin: Enhances gastrointestinal motility.

Clinical Implications

Abnormal secretion of GIT hormones can lead to various medical conditions, including gastric ulcers, irritable bowel syndrome, and obesity-related disorders. Understanding their physiological roles helps in the development of targeted therapies for these conditions.