Faculty Collaboration Database

Nitric oxide activates PKCalpha and inhibits Na+-K+-ATPase in opossum kidney cells. Am J Physiol 1999 Dec;277(6):F859-65

Date

12/22/1999

Pubmed ID

10600932

DOI

10.1152/ajprenal.1999.277.6.F859

Scopus ID

2-s2.0-0033370835 (requires institutional sign-in at Scopus site)   59 Citations

Abstract

Nitric oxide (NO) reduces the molecular activity of Na+-K+-ATPase in opossum kidney (OK) cells, a proximal tubule cell line. In the present study, we investigated the cellular mechanisms for the inhibitory effect of NO on Na+-K+-ATPase. Sodium nitroprusside (SNP), a NO donor, inhibited Na+-K+-ATPase in OK cells, but not in LLC-PK1 cells, another proximal tubule cell line. Similarly, phorbol 12-myristate 13-acetate, a protein kinase C (PKC) activator, inhibited Na+-K+-ATPase in OK, but not in LLC-PK1, cells. PKC inhibitors staurosporine or calphostin C, but not the protein kinase G inhibitor KT-5823, abolished the inhibitory effect of NO on Na+-K+-ATPase in OK cells. Immunoblotting demonstrated that treatment with NO donors caused significant translocation of PKCalpha from cytosolic to particulate fractions in OK, but not in LLC-PK1, cells. Furthermore, the translocation of PKCalpha in OK cells was attenuated by either the phospholipase C inhibitor U-73122 or the soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one. U-73122 also blunted the inhibitory effect of SNP on Na+-K+-ATPase in OK cells. The phospholipase A2 inhibitor AACOCF3 did not blunt the inhibitory effect of SNP on Na+-K+-ATPase in OK cells. AACOCF3 alone, however, also decreased Na+-K+-ATPase activity in OK cells. In conclusion, our results demonstrate that NO activates PKCalpha in OK, but not in LLC-PK1, cells. The activation of PKCalpha in OK cells by NO is associated with inhibition of Na+-K+-ATPase.

Author List

Liang M, Knox FG

MESH terms used to index this publication - Major topics in bold

Alkaloids
Animals
Arachidonic Acids
Carbazoles
Cell Line
Enzyme Activation
Enzyme Inhibitors
Estrenes
Indoles
Isoenzymes
Kidney
Kidney Tubules, Proximal
Kinetics
Naphthalenes
Nitric Oxide
Nitric Oxide Donors
Nitroprusside
Opossums
Protein Kinase C
Protein Kinase C-alpha
Pyrrolidinones
Sodium-Potassium-Exchanging ATPase
Staurosporine
Tetradecanoylphorbol Acetate