20 Gastrointestinal System Hormones Flashcards
To learn about GIS hormones (26 cards)
List 25 Gastrointestinal system hormones
- Gastrin
- Secretin
- Cholecystokinin
- Ghrelin
- Motilin
- Gastric inhibitory peptides
- Vasoactive intestinal polypeptide
- Somatostatin
- Substance p
- Enkephalin
- Neurotensin
- Serotonin
- Urogastrone
- Enterocrinin
- Villikin
- Galanin
- Glucagon like peptide 1
- Glucagon like peptide 2
- Leptin
- Neuropeptide Y
- Pancreatic polypeptide
- Trefoil peptide
- Growth Factors
- Enteroglucagon
- Bombesin
What cells secrete Gastrin
G-cells of antrum of pyloris glands of the stomach
What stimulates the production of Gastrin
- Presence of proteinous food in the stomach
- Local nervous plexuses
- Vasovagal reflexes
Physiological actions of Gastrin
- Stimulates Gastric acid secretion rich in pepsin and hydrochloric acid.
- Promote proliferation of Gastric epithelial cells.
- increased Gastric motility and rate of Gastric secretion.
- Stimulates Gastric emptying.
What is the first GIS hormone to be discovered, in what year and by who?
Secretin is the first GIS hormone to be discovered in 1902 by Bayliss and Sterling
What cells secrete secretin?
S-cells of the Duodenum
Secretin is produced in an inactive form called?
Prosecretin
Conversation of prosecretin to an active form occur in the presence of _________? in small intestine.
Acid Chyme
List the stimulants for secretion of secretin
- Acidity of the Chyme
2. Amino-acid
State the actions (functions) of secretin
- Stimulates exocrine pancreatic secretion of watery juice rich in bicarbonate ions
- Inhibits Gastric juice secretion
- Inhibits Gastric motility
- Augment the action of Cholecystokinin
Cholecystokinin is produced by what cells?
I-cells of duodenum, jejunum and ileum
Stimulants for secretion of Cholecystokinin includes?
- Fatty acids
- Peptides
- Amino-acid
Actions of Cholecystokinin
- Contraction of gallbladder
- Promote pancreatic scanty secretion rich in enzymes via second messenger- INOSITOL TRIPHOSPHATE
- Increases secretion of enterokinase
- Inhibits Gastric motility causing delayed emptying
- Augment contraction of pyloric sphincters
- Plays an important role in satiety and by suppressing hunger
- Induces drug tolerance to opoid
What cells secrete Ghrelin
Epithelial cells in the fundus of stomach
Small amount is also produced by hypothalamus, pituitary, kidneys and placental
Function of Ghrelin
Acts as a strong stimulant for appetite and feeding
What is Motilin
Is a 22 amino acid hormone,
It is secreted by Mo-cells of the stomach and small intestine and entero-chromaffin cells.
Functions of Motilin include?
- Involved in stimulating housekeeping pattern of motility
- Accelerate Gastric emptying
- Increase mixing and propulsive movements
- Increases peristalsis
Where are Gastric Inhibitory Peptides (G.I.P)
produced?
By K-cells in the duodenum, jejunum and antrum in the stomach
Stimulants for secretion of Gastric Inhibitory Peptides include?
- Acid Chyme
- Glucose
- Fats
Actions of Gastric Inhibitory Peptides include
- Inhibits Gastric secretion and motility
2. Potentiates release of insulin from beta cells in response to elevated glucose concentration
What are Vasoactive intestinal polypeptides (V.I.P) ?
A polypeptide secreted by cells in the stomach and small intestine
Stimulants for secretion of Vasoactive intestinal polypeptides (V.I.P)
Acid Chyme in the stomach
Physiological actions of Vasoactive intestinal polypeptides
- Stimulates insulin production
- Augment action of acetylcholine on salivart glands
- Dilates splanchnic blood vessels, inhibits hydrochloric acid secretion in Gastric juice
- Stimulates secretion of succus entericus with large amounts of water and electrolytes
What is Somatostatin
- A growth hormone Inhibitory hormone
- it is produced by D-cells of the stomachs small intestine and pancreas
- it is also produced by the hypothalamus
