Renal anion regulation Flashcards
What occurs if low Na+ detected?
1) Low body Na+
2) Low plasma volume
3) Low BP
4) GFR decreased- increase Na+ reabsorption
5) Less Na+ lost
What occurs if high Na+ detected?
1) High body Na+
2) Increase GFR
3) Decrease Na+ resabsorption
How are short term changes to BP made?
Changes GFR
How is BP regulated long term?
RAAS
What percentage of Na+ reabsorption occurs at:
Proximal tubule
Loop of Henle
Distal tubule
Collecting duct
Proximal tubule- 60%
Loop of Henle- 25%
Distal tubule- 10%
Collecting duct- 4%
What directly effects GFR?
Arterial blood pressure
What is GFR indirectly affected by?
Sympathetic nerves
Constrict arterials reduce blood entry into glomerulus
State one way GFR can be increased?
Aldosterone result in reabsorption Na+
What is most abundant intracellular ion?
K+
State 1 function K+?
Important regulation cardiac rhythm
Is majority K+ reabsorbed or excreted?
Reabsorbed 90%
Rest sweat/urine
How is K+ reabsorbed in collecting ducts?
Na/K ATPase pump
State 2 factors affect K+ secretion?
High K+ diet
Aldosterone stimulated if K+ too high
Increase secretion- eliminate excess
What is the juxtaglomerular apparatus composed of?
Afferent arteriole and distal convoluted tubule
What cells are present in afferent arteriole of juxtaglomerular apparatus?
Granular cells
Where are macula densa cells located?
Juxtaglomerular apparatus
Distal convoluted tubule
Where are granular cells located?
Juxtaglomerular apparatus
Afferent arteriole
