These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Intracellular pH regulation in the renal proximal tubule of the salamander. Na-H exchange.
    Author: Boron WF, Boulpaep EL.
    Journal: J Gen Physiol; 1983 Jan; 81(1):29-52. PubMed ID: 6833996.
    Abstract:
    Using pH-sensitive microelectrodes to measure intracellular pH (pHi) in isolated, perfused proximal tubules of the tiger salamander Ambystoma tigrinum, we have found that when cells are acid-loaded by pretreatment with NH+4 in a nominally HCO3--free Ringer, pHi spontaneously recovers with an exponential time course. This pHi recovery, which is indicative of active (i.e., uphill) transport, is blocked by removal of Na+ from both the luminal and basolateral (i.e., bath) solutions. Re-addition of Na+ to either the lumen or the bath results in a full pHi recovery, but at a lower-than-normal rate; the maximal rate is achieved only with Na+ in both solutions. The diuretic amiloride reversibly inhibits the pHi recovery when present on either the luminal or basolateral sides, and has its maximal effect when present in both solutions. The pHi recovery is insensitive to stilbene derivatives and to Cl- removal. A transient rise of intracellular Na+ activity accompanies the pHi recovery; there is no change of intracellular Cl- activity. These data suggest that these proximal tubule cells have Na-H exchangers in both the luminal and basolateral membranes.
    [Abstract] [Full Text] [Related] [New Search]