Where would paracellular movement of water be greater, in the small intestine or the large intestines?
In the small intestine.
The colon has "tight" tight junctions, and does not permit paracellular movement.
The jejunum is the major site of absorption for what electrolyte?
The enterocytes of the colon typically absorb what electrolyte, and secrete what other electrolyte?
The enterocytes of the colon typically secrete potassium and absorb sodium via the Na+/K+ channels.
Overall, the jejunum absorbs what compound?
Overall, the ileum absorbs what compound?
What two electrolytes are most often lost in severe diarrhea?
HCO3- / K+
What acid-base disturbance can occur in patients with severe diarrhea?
Hyperchloremic metabolic acidosis with normal anion gap.
What cells of the intestine secrete electrolytes and water, rather than absorb it?
Epithelial cells lining the intestinal crypts.
How does cholera toxin cause water loss?
Enters an enterocyte, inhibits the GTPase of the Gs protein coupled to adenylyl cyclase, causes the GTP to not be converted to GDP, causing Cl- channels to stay open, causing water loss.
With what are patients rehydrated after severe diarrhea?
Na+, Cl-, HCO3-, and glucose to stimulate the glucose-Na+ cotransporter.