Enteroendocrine hormones

Question 1

Gastrin

Answer 1

Site of production: Stomach mucosa
Stimulus: Food in stomach
Target & Action:
Stomach - increases secretion & increases churning
Small Intestine- stimulates contractions of intestinal muscle
Ileocecal valve- relaxes ileocecal valves
Large Intestine- stimulates mass movements

Question 2

Cholescystokinin

Answer 2

Site of production: Duodenal mucosa
Stimulus: Fatty chyme; partially digested proteins
Target & Action:
Stomach- inhibits churning
Liver/Pancreas- potentiate secretin’s actions
Gallbladder-stimulates organ to contract and release stored bile
Hepatopancreatic sphincters-relaxes sphincter to allow bile and pancreatic juice to enter duodenum
Pancreas-increases pancreatic juice

Question 3

Intestinal Gastrin

Answer 3

Site of production: Duodenal mucosa
Stimulus: food in duodenum
Target & Action:
Stomach-stimulates gastric glands and motility

Question 4

Secretin

Answer 4

Site of production: Duodenal mucosa
Stimulus: Acidic chyme
Target & Action : 
Stomach-inhibits secretions 
Liver-increases bile
Pancreas-increases pancreatic juice 
               -duct cells to release bicarbonate ion (HCO3)

Question 5

Vasoactive Intestinal Peptide

Answer 5

Site of production: Enteric neurons
Stimulus: Chyme
Target & Action:
Stomach- inhibits secretion
Small Intestine-stimulates buffer secretion, dilates intestinal capillaries
-relaxes intestinal smooth muscle
Pancreas- increases secretion

Question 6

Gastric Inhibitory peptide

Answer 6

Site of production: Duodenal Mucosa
Stimulus: fatty acids, amino acids, and glucose
Target & Action:
Stomach: inhibit hydrochloric acid production
Pancreas: stimulates insulin release