Digestive

Regulation of the Digestive System

Involves coordination of neural, local, and blood-borne signals that adjust motility and secretion based on the presence and composition of food.

Somatic Regulation

Involves voluntary control via motor neurons, primarily at the beginning and end of the digestive tract.

Autonomic Regulation

The process through which the Autonomic Nervous System modifies the activity of digestive organs from outside the gut wall.

Intrinsic Regulation

Also known as the Enteric Nervous System, it allows the digestive tract to regulate itself through local reflexes.

Paracrine Regulation

Involves chemical messengers produced by cells in the gut wall that act locally on neighboring cells.

Hormonal Regulation

Involves messengers secreted into the blood that travel to distant target organs to coordinate the digestive process.

Parasympathetic Division

Part of the Autonomic Nervous System that stimulates secretion and motility in the digestive system.

Sympathetic Division

Part of the Autonomic Nervous System that generally reduces peristalsis and secretory activity.

Enteric Nervous System

A complex network of neurons in the gut wall that controls digestive functions independently of the CNS.

Gastrin

A hormone secreted by the stomach in response to proteins; stimulates release of HCl and pepsinogen.

Secretin

Hormone released by the small intestine when acidic chyme arrives; stimulates pancreas to release bicarbonate.

Cholecystokinin (CCK)

Hormone secreted by the duodenum in response to fats and proteins; triggers gallbladder contraction and enzyme release.

Hydrochloric Acid (HCl) Production

Stimulated by gastrin, histamine, and acetylcholine; regulated by negative feedback when pH drops too low.

Zymogens

Inactive forms of digestive enzymes secreted by the pancreas to prevent tissue digestion.

Pacemaker Activity

Generated by interstitial cells of Cajal (ICC) producing slow waves that trigger smooth muscle contractions.

Segmentation

Rhythmic contractions in the small intestine that mix chyme with digestive juices.

Peristalsis

Wave-like contractions that move contents through the digestive tract.

Enterogastrones

Hormones like CCK and GIP that signal the stomach to slow down its activity when the intestine is full.

Glucose Homeostasis

The liver removes excess glucose from the blood and converts it to glycogen for storage.

Detoxification

The liver processes harmful substances via bile, immune cells, or chemical changes to reduce toxicity.