Flashcards in Final Exam GI Physiology: Glandular Stomach Deck (39)
What protects the glandular stomach against microorganisms?
What protects the glandular stomach against HCl and abrasive ingesta?
What is responsible for lubrication of the glandular stomach?
The glandular stomach is the initial site of ______ of protein.
The glandular stomach functions to produce and secrete GIF (gastric intrinsic factor). What is the function of GIF?
It binds to Vitamin B12 and protects it from being digested
What secretes GIF?
The acinar cells of the exocrine pancreas
What is Vitamin B12 essential for?
The maturation of RBCs
What are the types of cells found in the glandular stomach?
Peptic Chief Cells
Parietal Oxyntic Cells
Mucus Neck Cells
What do peptic chief cells do?
Produce enzymes likes pepsinogen, lipase, prorennin, and urease. Little water follows.
What do parietal oxyntic cells do?
Produce HCl and GIF. Water follows.
What do mucus neck cells do?
Produce mucin and HCO3-. Water follows.
HCO3- production is increased by what?
Cholinergic agents and prostaglandins
HCO3- production is decreased by what?
alpha- adrenergic agonists and phospholipase A2 and COX inhibitors
Parietal cells actively transport _____ and ______.
H+ and Cl-
What is alkaline tide?
The alkaline blood leaving the stomach is called alkaline tide.
What are the 3 powerful AGONISTS of parietal cell HCl secretion?
What are some endogenous ANTAGONISTS of parietal cell HCl secretion?
What does ACh act on?
What does ACh inhibit?
Inhibits secretion of somatostatin
What does ACh promote?
Promotes the secretion of histamine and gastrin
What does Histamine act on?
Where is Gastrin produced?
From G-cells in the gastric and duodenal mucosa
What does Somatostatin inhibit?
Inhibits release of gastrin
What does CCK do?
Acts to decrease acid by binding to gastrin/CCK receptors with little excitation
Where is secretin produced?
It is an endocrine product of the duodenal mucosal cells
What drugs influence parietal cell activity and therefore production/secretion of HCl?
H2 Receptor Blockers
Inhibitors of H+-K+ ATPase
What does the administration of glucocorticoids/COX inhibitors do?
Increase acid production/secretion
In general, the cephalic phase and gastric phase of glandular stomach activity are _________.
In general, the intestinal phase of glandular stomach activity is ________.