Ion Pumps Of The Cell Membrane

Question 1

What are the functions of the Na+/K+/ ATPase pump?

Answer 1

Forms the Na+ and the K+ gradients, which are nesscary for electrical exitability , drives secondary active transport, involved in the regualtion of cell volume and cells signal by small changes in the intracellular Ca2+

Question 2

What are some of the features of the sodium/ calcium exchanger? NCX

Answer 2

Exchanges 3Na+ for 1Ca2+, electrogenic current that flows int eh direction of the Na+ gradient, role in expelling the intracellular Ca2+ and within the cell recover, and has a passing role in cell toxicity during Ischameia repurfusion injury as it can reverse. has Low affinity but high capacity

Question 3

What are some of the roles of the Na+/H+ exchanger?

Answer 3

Is an electroneutral 1:1 exchange, regulates cell pH, cell volume, extracellular Na+ is exchanged for intracellular H+, activated by the different growth factors, inhibited by amiloride

Question 4

What are the mechanisms to resist cell swelling?

Answer 4

The extrusion of osmotically active ions, which has to be done in a electrocnetural fashion

Question 5

What channels are involved in Na+ reuptake in the thick ascending limb?

Answer 5

NKCC2 which is a symport for Na+ and2Cl-, ROMK which removes calcium into the lumen, and ions are removed intot eh blood by KClCT, ClCk-b and the Na pump

Question 6

What drugs effect Na+ reuptake in the thick ascending limb?

Answer 6

Loop directuics inhibit NKCC2

Question 7

What are some of the channels invoeld in Na+ reuptake by the kidney in the distal convoluted tube?

Answer 7

NCCT (symport for sodium and cholride), TRPM6 , and ENaC

Question 8

What drugs act on the sodium reputake in the distal convoluted tubule of the kidney?

Answer 8

NCCT is inhibited by thiazides, ENaC is inhibited by amilorides