Intro To Renal - Random
What tracers are used for Total Body Water (TBW)?
1) Antipyrine 2) D2O
What tracers are used for Extracellular Fluid (ECF)?
1) Inulin 2) Radioactive sulfate
What tracers are used for Plasma Volume (PV)?
1) Radioactive albumin 2) Evan's blue
What percentage of total body weight does interstitial fluid account for? Which fluid compartment is it a part of?
15% of total body weight Extracelullar fluid
What percentage of cardiac output does the kidney receive?
20%
What percentage of total body weight does extracellular fluid account for?
20% of total body weight
What is the normal ECF (and ICF) osmolarity?
290 mosm/L
What percentage of total body weight does intracellular fluid account for?
40% of total body weight
What percentage of total body weight does plasma volume account for? Which fluid compartment is it a part of?
5% of total body weight Extracelullar fluid
What percentage of total body weight does water account for?
60% of total body weight
How do the kidneys regulate fine control of Na+ content?
By regulating the renal reabsorption of Na+.
What ions is Na+ primarily balanced by?
Cl- and HCO3-
What compartment shrinks when someone has diarrhea?
ECF
What compartment shrinks when someone has dehydration?
ECF and ICF
Which will stimulate ADH release -- high or low plasma osmolarity?
High plasma osmolarity
What compartment grows when someone has a lack of aldosterone?
ICF
Drinking pure water (no salt) after sweating profusely will have what effects on ICF and ECF?
ICF will increase, ECF will decrease
Is Na+ secreted from the kidneys or is it filtered out?
It is filtered out, not secreted
What is the major determinant of osmolarity?
Na+ concentration
When the Na+ reabsorption by THESE epithelial cells increases, there is a simultaneous increase of their secretion of K+ to the tubular fluid
Principal cells in the collecting ducts
Are the majority (~87.5%) of nephrones short, Superficial cortical nephrons or large, long Juxtamedullary nephrons?
Superficial cortical nephrons
Which segment of the nephron normally reabsorbs about 15-20% of the water that was filtered into the tubules?
Thin descending loop
What plays a major role in the high osmolarity ofthe medullary interstitial fluid (and allows us to conserve water by excreting a small volume of concentrated urine)?
Urea