Renal-Chapter 30 Potassium Flashcards
Is K+ found more inside or outside the cell?
98 percent intracellular
2 percent extracellular
If K+ ECF values are too high what is it called?
hyperkalemia
If K+ ECF values are too low what is it called?
Hypokalemia
How would unbalanced K+ effect the heart?
Affects the membrane potential and could cause heart problems
What are 4 things that stimulate K+ uptake by cells and decrease extracellular K+
Insulin
Aldosterone
Beta adrenergic (epinephrine)
Alkalosis
What are some things that can cause hypokalemia?
Too much aldosterone
What are some things that can cause hyperkalemia?
Too little aldosterone
Beta blockers
What are 7 things that increase ECF K+ and shift K+ out of cells
Cell lysis
Strenuous exercise
Increased ECF osmolarity
Acidosis
Insulin deficiency (diabetes mellitus)
Aldosterone deficiency (Addison’s disease)
Beta blockers
What is the important area of the nephron that has principal cells and plays major role in K+ secretion
DCT and CCD
What are the important channels that secrete K+ from prinicipal cells to tubular lumen?
BK and ROMK
What role does intercalated cells have wth K+ depletion and excess?
K+ depletion
Type A will reabsorb via H+/K+ ATPase and K+ channel
K+ xs
Type B will secrete via H+/K+ ATPase and K+ channel
What are 4 things that will stimulate K+ secretion
What is stimulated when K+ secretion is stimulated
Increased ECF K+
Increased aldosterone
Increased tubular flow rate
Alkalosis
Na+/K_ pumps are stimulated when K+ secretion is stimulated
What can decrease K+ secretion
Acidosis
T/F Small changes in ECF K+ causes small changes in aldosterone concentration
False
LARGE changes
In the past, what were our K+/Na+ diets like?
Now?
Past= high K+/low Na+
Now= low K+/high Na+
hypertension, kidney and cardiovascular disease
