Water And Na+ Balance Flashcards
Regulated water reabsorption occurs in the medullary collecting duct, and depends upon the vertical osmotic gradient in the medulla.
What is the role of the loop of Henle? (2)
What is the role of the collecting duct? (2)
The medullary osmotic gradient depends on the anatomical arrangement of what two things together? How does it work together to achieve this? (Terminology not mechanism)
Vasa recta: blood vessels parallel to loop of Henle.
This allows for countercurrent exchange.
Explain how countercurrent exchange works. What does it enable?
Enable trapping of stuff!
Describe the parts that make the Loop of Henle:
What is notable about the thick ascending limb? (2)
What is notable about the descending limb? (2)
Where do loop diuretics target?
Loop diuretics inhibit sodium reabsorption.
Explain how countercurrent exchange works in the Loop of Henle?
Water reabsorbed in descending limb because a lot of Salt comes out of ascending limb. Ascending limb can re uptake salt after this but no water.
Explain how countercurrent multiplication works,
Using:
Single effect:
Flow of fluid:
Higher number= Saltier (more ions)
So the more loops the more salty, and the LONGER the loop more salty.
How can water leave the descending limb and not destroy the osmotic gradient?
Remember blood vessels and loop of Henle go opposite directions!
permeability to water and solutes in the distal tubule and collecting duct is regulated by what hormone?
Vasopressin
The kidneys produce either concentrated or dilute urine by regulating water permeability in the what?
Define AQP-3 and AQP-2. Where they are located and when they are present.
Vasopressin is secreted by what types of cells and where are they released?
What stimulates Vasopressin? Where is the stimulator located?
Extra: what are 2 other names it’s called?
Other 2 pathways occur when blood pressure is low.
Is this picture showing pathway when thirsty or hydrated? What would the other pathway not directed look like?
Define AVP-D and AVP-R:
What is the issue?
What causes it?
How is it treated?
What symptom do they both cause?
(Used to be called diabetes insípidos)
What cotransporter is in what part of the nephron:
Proximal tubule:
Thick ascending loop of Henle:
Distal tubule:
Cortical collecting duct:
What ion do they all affect and why?
ECF volume/ osomolarity is regulated by Sodium secretion and reabsorption.
What are the 3 proteins involved in regulating Na+ reabsorption in the cortical collecting duct? Where are they located? What hormone stimulates all of them?
What system is Aldosterone apart of? (What makes it?)
Hint: has easy abbreviated name.
What is the general thing Aldosterone stimulates? And where?
Where is it released too?
Decreased blood pressure triggers renin release in three ways.
What are those 3 ways? (Details on all 3 will be on later FC’s)
Decreased blood pressure triggers renin release in three ways. 1 way: decreased Na+ in the distal tubule .
How does it work?
Sensed by macula densa (low Na+), via paracrine signaling mechanism sending message to Afferent arrieral which have granule cells the release renin.
Decreased blood pressure triggers renin release in three ways. 1 way: decreased stretch in the afferent arteriole.
How does it work?
Low BP directly makes the Afferent arteriole stretch. The granules are stretch sensitive, so they release renin when low stretched. (NOT long stretched)
Decreased blood pressure triggers renin release in three ways. 1 way: sympathetic nervous system input to the afferent arteriole
Explain how it works.
blood pressure sensors activate cardiovascular control center to activate SNS
Summary slide:
