Lec 4/5 - 4 Renal Water Balance Flashcards
normal excrete solute is blank mOsmol/day
600
osmolality is pretty much equal to osmolarity but the units are blank not blank
mOsmol/kg, mOsmol/L
urine osmolarity equation
Uosm = Osmol excreted per day / V
V= urine flow
urine osmolarity can be as low as blank
30 mOsm
urine osmolarity can be as high as blank
1200 mOsm
starting point for urine production by the kidney
filtered blood plasma
osmolality of blood plasma is maintained at blank
300 mOsm
kidneys can dilute the urine blank fold but can concentrate the urine only blank fold
10, 4
urine flow formula
V = Cosm + Ch2o
Cosm is the osmolar clearance and is the hypothetical blank necessary to dissolve all the excreted solutes at a concentration that is isosmotic with blood plasma
volume/day
tubule that reabsorbs 2/3 of the filtered fluid isosmotically
proximal
the blank limb of the loop of henle reabsorbs salt in excess of h2o
thick ascending limb
tubule fluid is diluted along blank
the loop of Henle
whether the final urine remains dilute or is concentrated depends on whether water reabsorption occurs in the blank
collecting tubule
water permeability of the collecting duct is blank
low
the continued reabsorption of NaCl along the distal nephron leaves a relatively blank fluid behind in the tubule lumen
hypotonic
peptide hormone that stimulates water reabsorption by the kidney
adh
adh increases the water permeability of blank
the collecting duct
adh increases the movement of blank to the plasma membrane to increase water permeability
aquaporins
decrease in blood pressure or volume stimulates blank release to blank
adh, increase volume via reabsorption
diabetes mellitus can lead to blank in the urine because the kidney cant reabsorb all of it and will produce blank urine because of all the solute
glucose, tons of urine
this disease is characterized by not being able to reabsorb h2o in the collecting duct and individuals have excessive thirst and make excessive amounts of urine and become rapidly dehydrated…. not enough adh being produced
diabetes insipidus
diabetes insipidus easy fix
adh drugs
disease that is the failure of the kidney to respond to adh and is a mutation in aquaporin 2
nephrogenic diabetes insipidus
opposite of diabetes insipidus when the body retrieves too much water from the tubule leading to water toxicity
syndrome of inappropriate adh secretion
tissue that surrounds the medullary segments of the nepron
medullary interstitium
fluid in the medullary interstitium is enriched in these
Na, Cl, urea
the loop of henle removes more blank than blank from the lumen
NaCl, water
two components to generating the gradient
single effect, countercurrent multiplier
single effect has the blank actively pumping NaCl into the interstitium
thick ascending limb
the countercurrent multiplier multiplies the blank to produce a far greater blank between the cortex and medulla
single effect, mOsm gradient
collecting duct has the ability to do this
concentrate urine
urea is freely filtered at the blank but 85 percent is reabsorbed along the blank
glomerulus, nephron
urea comes from blank breakdown
protein
protein rich diet results in blank urine
more concentrated
blood supply to the medulla is relatively blank which reduces the contribution to medullary washout
minimal
these create an efficient countercurrent exchange mechanism with the loop of henle which minimizes washout even more
vasa recta
amount of water is properly balanced
euvolemia
main contributor to extracellula osmolarity because it is the main osmolyte in extracellular fluid
sodium
volume expansion during positive sodium balance
hypervolemia
volume contraction in negative sodium balance
hypovolemia
