Gastric secretions Flashcards
what cell is the source of HCl?
parietal cell
what cell is the source of intrinsic factor?
parietal cell
what cell is the source of pepsinogen?
chief cell
what cell is the source of mucus and bicarb?
superficial epithelial cell
what cell is the source of histamine in the GI tract? what is the function of histamine in the GI tract?
- ECL cells 2. promotes HCl secretion
what cell is the source of gastrin secretion? what is the function of gastrin in the GI tract?
- G cell 2. promote HCl secretion
what cell is the sourse of Ach secretion? what is the function of Ach in the GI tract?
- nerve cell 2. promote mucus / bicarb / HCl secretion
what cell is the source of somatostatin? what is the function of somatostatin in the GI tract?
- D cells 2. suppress HCl secretion
what cells are found in the body of the stomach?
parietal, chief, neck, ECL
what cells are found in the antrum of the stomach?
chief, endocrine (G and D cells)
what cells are found throughout the entire stomach?
superficial epithelial cells
what are the two types of gastric secretions?
sodium rich from non-parietal cells and proton rich from parietal cells
acid secretion is regulated through which pathways?
- paracrine (histamine) 2. endocrine (gastrin) 3. neuronal (Ach)
what is the function of PGs in relation to acid secretion?
inhibit acid secretion (paracrine)
how do gastrin and Ach indirectly stimulate acid secretion?
via stimulation of gastrin-producing G cells and histamine-producing ECL cells, respectively
what hormone turns off acid secretion?
somatostatin
where does intrinsic factor bind vitamin B12?
duodenum
what is the primary signal for pepsinogen secretion?
Ach
what is the neurocrine signal for mucus secretion? paracrine signal?
1 .Ach 2. PGs
what are the roles of PGs in the GI tract?
- mucus and bicarb secretion 2. suppression of HCl secretion 3. increased gastric blood flow
