Medullary Conc Gradient

0.0(0)
studied byStudied by 0 people
learnLearn
examPractice Test
spaced repetitionSpaced Repetition
heart puzzleMatch
flashcardsFlashcards
Card Sorting

1/10

encourage image

There's no tags or description

Looks like no tags are added yet.

Study Analytics
Name
Mastery
Learn
Test
Matching
Spaced

No study sessions yet.

11 Terms

1
New cards

to maintain water balance or homeostasis, kidneys need to be able to secrete urine that is sometimes? How when water only moves by osmosis?

  • less concentrated (dilute, <300_)

  • more concentrated than plasma (conc. > 300)

  • countercurrent multiplication

2
New cards

goals of countercurrent multiplication

compared to plasma:

  • dilute tubular fluid

  • To make medullary intersitial fluid to be concentrated

3
New cards

because of the way loop of henle is designed:

  • 1st end result: exrete dilute:

    • at the turn, filtrate is concentrated

    • more NaCl leaves than H2O

  • 2nd end result: excrete concentrated urine

4
New cards

Body can excrete either dilute or concentrated urine, because of the ?

  • countercurrent mechanism: Loop of henle

    • dilutes tubular fluid

    • concentrates medullary intersitiam (concentrated urine)

  • Variable permeability of collecting duct to water

5
New cards

__ controls the water permeability of collecting duct: how?

antidiuretic hormone

  • collecting duct is impermeable to water: dilute urine

    • NO ADH → no channels on luminal membrane (#2)

  • Collecting duct is permeable → concentrated urine:

    • ADH: Aquaporin 2 = aquaporinin channel on luminal membrane

6
New cards

ADH activation

  • adh binds to V2 receptor on basolateral side of cell

  • Aquaporin 2 on luminal side is activated

7
New cards

because of the countercurrent mechanism:

medullary intersitium is increasingly concentrated

8
New cards

With ADH and water channels, water continues to be reabsorbed as ?

filtrate goes down collecting duct, due to the medullary interstitium increasinly concentrated

9
New cards

With no ADH: osmolairty is ?

max ADH + max osmolarity is ?

50, no aquaporins, very hydrated

1200, dehydrated, many aquaporins

10
New cards

in presence of ADH, what will happen to urine?

  • smaller volume of more concentrated uirne

11
New cards

normal 24 hour urine osmolarity average

500-800