EurekaMag.com logo
+ Site Statistics
References:
52,725,316
Abstracts:
28,411,598
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Regulation of intracellular ph in llc pk 1 cells by sodium hydrogen exchange


Journal of Membrane Biology 93(1): 33-42
Regulation of intracellular ph in llc pk 1 cells by sodium hydrogen exchange
Suspensions of LLC-PK1 cells (a continuous epitheliod cell line with renal characteristics) are examined for mechanisms of intracellular pH regulation using the fluorescent probe BCECF. Initial experiments determine suitable calibration procedures for use of the BCECF fluorescent signal. They also determine that the cell suspension contains cells which (after 4 hr in suspension) have Na+ and K+ gradients comparable to those of cells in monolayer culture. The steady-state intracellular pH (7.05 .+-. 0.01, n=5) of cells which have recovered in (pH 7.4) Na+-containing medium is not affected over several minutes by addition of 100 .mu.M amiloride or removal of extracellular Na+ .**GRAPHIC**. < 1mM. In contrast, when the cells recover from an acid load (caused by NH4 preincubation and removal), the recovery is largely Na+ dependent and is sensitive to 100 .mu.M amiloride. These results suggest that with resting pH near neutrality, both .**GRAPHIC**. and .**GRAPHIC**. exchange reactions are functionally inactive (compared to cellular buffering capacity). In contrast .**GRAPHIC**. exchange is activated by an increased cellular acid load. This activation may be observed directly either as a stimulation of net H+ efflux or net Na+ influx with decreasing intracellular pH. The extrapolation of this latter data suggests a "set point" of Na+/H+ exchange of approximately pH 7.0, consistent with the observed resting intracellular pH of approximately 7.05.


Accession: 006288864



Related references

Regulation of intracellular ph in a10 vascular smooth muscle cells evidence for sodium hydrogen exchange and chlorine bicarbonate exchange. Pfluegers Archiv European Journal of Physiology 411(SUPPL 1): R203, 1988

Sodium hydrogen exchange in cultured chick heart cells intracellular ph regulation. Journal of General Physiology 85(1): 43-64, 1985

Regulation of sodium hydrogen exchange in the rat papillary collecting duct by intracellular sodium. Kidney International: 442, 1987

Intracellular pH in vascular smooth muscle: regulation by sodium-hydrogen exchange and multiple sodium dependent HCO3- mechanisms. Cardiovascular Research 29(2): 239-246, 1995

Evidence for basolateral sodium hydrogen ion exchange in frog skin epithelium and its role in sodium transport and intracellular ph regulation. Journal of Physiology (Cambridge) 382: 137P, 1987

Intracellular ph regulation via sodium hydrogen exchange in vertebrate rod photoreceptors. Investigative Ophthalmology & Visual Science 28(3 SUPPL): 354, 1987

Intracellular ph in human arterial smooth muscle regulation by sodium ion hydrogen ion exchange and a novel 5 n ethyl n isopropylamiloride sensitive sodium and bicarbonate dependent mechanism. Circulation Research 67(4): 814-825, 1990

Sodium hydrogen exchange activity in hepatocytes its role in regulation of intracellular ph. Hepatology 7(5): 1038, 1987

Sodium hydrogen exchange is down regulated in confluent vascular smooth muscle cells vsmcs due to low affinity for intracellular hydrogen ions. Kidney International 35(1): 306, 1989

Regulation of intracellular ph in balb c 3t3 cells bicarbonate raises ph via sodium bicarbonate hydrochloric acid exchange and attenuates the activation of sodium ion proton exchange by serum. Journal of Biological Chemistry 266(3): 1551-1556, 1991