Serotonin as an inhibitor of gastrin

R P Saik1

  • 1Dept. of Surgery, VA Medical Center, San Diego, California 92161, USA.

Related Concept Videos

Drugs Affecting GI Tract Motility: Serotonin Receptor Agonists01:23

Drugs Affecting GI Tract Motility: Serotonin Receptor Agonists

Serotonin, a crucial neurotransmitter synthesized by enterochromaffin cells, plays a cardinal role in regulating gastrointestinal (GI) motility. With over 90% of the body's total serotonin in the GI tract, its influence on digestive processes is profound. Serotonin is swiftly released upon various stimuli, such as food boluses or certain drugs, triggering intrinsic sensory neurons in the myenteric plexus and extrinsic vagal and spinal sensory neurons. This leads to the activation of the...
Intestinal Phase of Digestion01:29

Intestinal Phase of Digestion

The intestinal phase of digestion is the third and final stage of the digestive process, occurring after the cephalic and gastric phases. It begins when chyme, a partially digested mixture of food and digestive enzymes, enters the small intestine from the stomach. This phase is crucial for nutrient absorption and involves complex hormonal and enzymatic interactions.
The arrival of the chyme in the small intestine distends the duodenum, which triggers the enterogastric reflex. This distension...
Acid Suppressive Drugs for Peptic Ulcer Disease: Histamine H2-Receptor Antagonists01:28

Acid Suppressive Drugs for Peptic Ulcer Disease: Histamine H2-Receptor Antagonists

Histamine H2 receptors, which are intricately located on the basolateral membrane of parietal cells, play a crucial role in modulating gastric acid secretion. When released from enterochromaffin-like cells, histamine engages H2 receptors, initiating the cyclic AMP (cAMP) pathway. In this pathway, adenylyl cyclase converts ATP into cAMP, elevating intracellular cAMP levels. The activation of protein kinase A follows, stimulating the proton pump. This stimulation prompts the secretion of hydrogen...
G-protein Coupled Receptors01:21

G-protein Coupled Receptors

G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
Pathophysiology of Peptic Ulcer Disease: Injurious Factors01:22

Pathophysiology of Peptic Ulcer Disease: Injurious Factors

Peptic ulcers are sores on the stomach's inner lining and the upper small intestine, which are the result of disruptions in the mucosal layer that houses parietal cells which produce gastric acid, and chief cells which secrete pepsinogen.
In the antrum region, G cells secrete the gastrin hormone that binds to gastrin-cholecystokinin-B (CCK2) receptors on parietal and enterochromaffin-like (ECL) cells in the fundic glands. Simultaneously, the vagus nerve releases acetylcholine, which binds to M3...
Hormonal Regulation01:40

Hormonal Regulation

Hormones regulate a significant portion of digestion through activation of the neuroendocrine system. The neuroendocrine system of digestion contains many different hormones all with multiple functions that are both, directly and indirectly, involved in digestion.