Na(+)-K(+)-ATPase in frog esophagus mucociliary cell membranes: inhibition by protein kinase C activation

The American Journal of Physiology
I GertsbergM Danilenko

Abstract

We examined protein kinase C (PKC)-dependent regulation of Na(+)-K(+)-ATPase in frog mucociliary cells. Activation of PKC by 12-O-tetradecanoylphorbol-13-acetate (TPA) or 1,2-dioctanoyl-sn-glycerol (diC8) either in intact cells or isolated membranes resulted in a specific inhibition of Na(+)-K(+)-ATPase activity by approximately 25-45%. The inhibitory effects in membranes exhibited time dependence and dose dependence [half-maximal inhibition concentration (IC50) = 0.5 +/- 0.1 nM and 2.4 +/- 0.2 microM, respectively, for TPA and diC8] and were not influenced by Ca2+. Analysis of the ouabain inhibition pattern revealed the presence of two Na(+)-K(+)-ATPase isoforms with IC50 values for cardiac glycoside of 2.6 +/- 0.8 nM and 409 +/- 65 nM, respectively. Most importantly, the isoform possessing a higher affinity for ouabain was almost completely inhibited by TPA, whereas its counterpart was hardly sensitive to the PKC activator. The results suggest that, in frog mucociliary cells, PKC regulates Na(+)-K(+)-ATPase and that this action is related to the specific Na(+)-K(+)-ATPase isoform.

References

Dec 15, 1991·Proceedings of the National Academy of Sciences of the United States of America·A M BertorelloP Greengard
May 1, 1990·The American Journal of Physiology·J L Brodsky
Jan 1, 1988·Methods in Enzymology·J G Nørby
Jul 1, 1985·The American Journal of Physiology·D EshelZ Priel
Jun 9, 1995·The Journal of Biological Chemistry·M S Feschenko, K J Sweadner
Feb 10, 1995·The Journal of Biological Chemistry·G FisoneP Greengard
Nov 15, 1993·Biochemical and Biophysical Research Communications·M DanilenkoY Sharoni
Feb 1, 1993·The Journal of Clinical Investigation·T SatohA I Katz

❮ Previous
Next ❯

Citations

Aug 16, 2000·American Journal of Physiology. Cell Physiology·A G Therien, R Blostein
Jul 1, 2006·The Journal of Experimental Biology·Owen M Woodward, A O Dennis Willows

❮ Previous
Next ❯

Related Concepts

Related Feeds

Cardiac Glycosides

Cardiac glycosides are a diverse family of naturally derived compounds that bind to and inhibit na+/k+-atpase. Discover the latest research on cardiac glycosides heres.