Gastric Secretions Flashcards
List the secretions of the Parietal cells
Release HCL
and
Intrinsic factor.
List the secretions of the chief cell and what chemical activates it.
Chief cells release pepsinogen in response to Ach stimulation.
List the secretions of the Neck and superficial epithelial cells
Produce mucin and bicarb for protection.
Can secrete pepsinogen as well!
List the secretions of the Enterochromaffin like cells ECL and the stimulant
Stimulated by Gastrin and Ach, these release histamine which increases HCL production.
List the secretions of the G - epithelial cells
Where are they found?
These are endocrine cells in the antrum of the stomach.
Stimulated by peptones and amino acids causing the production of Gastrin by the Vagal nerve.
List the secretions of the D epithelial cell
These are endocrine cells in the antrum as well as respond to low pH by secreting somatostatin which ultimately inhibits G cells.
Which neuronal pathways control stomach acid secretion?
Ach from the ENS or PNS can act directly on parietal cells or indirectly to produce HCL.
Which Paracrine pathways control stomach acid secretion?
Histamine from ECL cells stimulate the H+/K+ ATPase.
Prostaglandins stop the H+/K+ ATPase.
What are some endocrine pathways that control stomach acid secretion?
Gastrin from the G cells can bind to directly to parietal cell and stimulate HCL or indirectly bind ECL cells stimulating HCL through histamine release.
What compound can be used to inhibit the release of HCL from the stomach?
Prostaglandins can inhibit the release of HCL from the parietal cells.
what occurs during the interdigestive phase of gastric acid secretion?
This has the lowest HCL secretion in the morning and slowly rises through the day.
What occurs during the cephalic phase of gastric acid secretion?
Accounts for 30% of the acid secreted via parasympathetic response and is stimulated by the sight, sound, or smell of food.
What occurs during the gastric phase of gastric acid secretion?
Stimulated by distention of the stomach and protein in the stomach leading to acid secretion by parasympathetic control.
What occurs during the intestinal phase of gastric acid secretion?
10% of all secretions occur here.
It is stimulated by peptides or amino acids in the duodenum which stimulates Gastrin release.
Where is intrinsic factor released and where does it interact with vitamin B12?
Released by the parietal cells where it will bind vitamin B12 in the duodenum.
