Flashcards in Wk3 H20, Electrolyte, Intestinal Motility Deck (24)
substance that promotes bowel loosening and movement
feeling of needing to pass stool even when bowel is empty
Location of cells that absorb fluid:
tips of villi
Location of cells that secrete fluid:
How does sodium get in apical side for water to follow?
(sodium hydrogen exchanger)
How does chloride get in apical side to join sodium and water follow?
Electrogenic uptake of water?
Na+ / Glucose (SGLT1-apical) (GLUT-2, basolateral)
**Cl- and H20 follow passively via tight junctions
long reflex regulator of Cl- secretion:
GI peptide in goblet and ECL cells
promotes Cl- secretion via CFTR
Drug that activate guanylate cyclase type C to treat constipation:
The bulk of fluid reabsorption is driven by?
Nutrient-coupled electrogenic sodium absorption
How does sodium enter COLONOcytes?
mostly in distal colon
What stimulates ENaC expression in colonocytes?
just like the kidney!
How does electroneutral NaCl absorption occur n the colon?
Name some secretagogues (enhance secretion)
Name some absorbagogues (enhance absorption):
Diarrhea from excess secretion of CL-?
Diarrhea from poor absorption of nutrients?
What regulates intestinal motility?
BER (basal electric rhythm) --- cells of Cajal?
Enteric nervous system
BER cycle rate in jejunum vs ilium?
jejunum -- 12/min
distal ilium -- 8/min
See slide 31 and 35
for specific regulators of motility
BER at ileocecal valve vs sigmoid colon:
IC valve -- 2/min
SC -- 6/min
Excess production of what causes Inlammatory Bowel Disease sx?
**caused by Crohn's or ulcerative colitis