Quantcast

alpha intercalated cells of neprhone

This forum made possible through the generous support of SDN members, donors, and sponsors. Thank you.

Onigiri

Full Member
2+ Year Member
Joined
Nov 30, 2015
Messages
72
Reaction score
6

Members don't see this ad.
I was wondering why a negative lumen from aldosterone would increase H+ Atpase activity in the alpha intercalated cells in the kidney and why this increase in H+ Atpase activity increases HCO3-/Cl- exchange, from first aid 2017 explanation?

Thank you in advance.
 

slowlybutshelly

ms4
10+ Year Member
Joined
Nov 14, 2009
Messages
505
Reaction score
19
I am interested in this question also. First off; is this a question from where? Looking at first aid, I think the negativity of a lumen would draw +ions into the lumen and thus make the Hatpase work faster. The HCO3/Cl exchanger is going on in the Beta intercalated cells which didnt seem to exist when I last took Step1 in 2004. anyone else.
 

iBS1972

Full Member
Joined
May 24, 2017
Messages
248
Reaction score
85
I was wondering why a negative lumen from aldosterone would increase H+ Atpase activity in the alpha intercalated cells in the kidney and why this increase in H+ Atpase activity increases HCO3-/Cl- exchange, from first aid 2017 explanation?

Thank you in advance.

Let's review the effects of aldosterone:
--stimulation of basal Na/K-ATPase
--increased insertion of apical ENaC
--increased insertion of apical K+ leak channels
1. Why a negative lumen from aldosterone would increase H+ Atpase activity in the alpha intercalated cells in the kidney? Slowlybutshelly has the right idea. Increased Na resorption leads to a negative lumen, which helps H-ATPase pump H+ out. (This is interesting, because it is an active transport, so theoretically it shouldn't affected by electrochemical gradient, but this was what I was taught as well.)
2. This increase in H+ excretion leads to increased resorption of H2O and CO2 (which forms HCO3- and H+ via carbonic anhydrase). The HCO3- is absorbed via BASAL HCO3-/Cl- exchange. The H+ is pumped out via APICAL H-ATPase and H+/K+ exchange.

Edit: The increased H+ excretion leads to more H2O and CO2 via luminal carbonic anhydrase, and this H2O and CO2 is resorbed by passive transport.
 
  • Like
Reactions: 1 user
Top