Indomethacin alters the Na,K-ATPase response to protein kinase C activation in cultured rabbit nonpigmented ciliary epithelium

Nicholas A Delamere, James Parkerson, Yining Hou

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Purpose. To test whether prostaglandin E2 (PGE2) is generated by cultured nonpigmented ciliary epithelial (NPE) cells treated with the phorbol ester, phorbol dibutyrate (PDBu), an activator of protein kinase C. In addition, the authors tested whether indomethacin, a cyclooxygenase inhibitor, influences the stimulation of active sodium-potassium transport observed in PDBu-treated cells. Methods. A cell line derived from rabbit NPE was used in this study. PGE2 was measured by an enzyme-linked immunosorbent assay technique. Ouabain-sensitive potassium (86Rb) uptake was measured as an index of active sodium-potassium (Na,K-ATPase-mediated) transport. Ouabain-sensitive ATP hydrolysis (Na,K-ATPase activity) also was measured. Cell sodium and potassium content was determined by atomic absorption spectrophotometry. Results. Marked PGE2 generation was observed in PDBu- treated cells. Indomethacin abolished the PGE2 response. Ouabain-sensitive potassium (86Rb) uptake was stimulated ~40% in cells exposed to PDBu, but a stimulation of >100% was observed in cells exposed to PDBu in the presence of indomethacin. Added alone, indomethacin did not alter ouabain-sensitive potassium (86Rb) uptake. Neither nordihydroguaiaretic acid (a lipoxygenase inhibitor) nor ethoxyresorufin (a cytochrome P450 inhibitor) altered the 86Rb uptake response to PDBu. Sodium and cyclic adenosine monophosphate content was unchanged in cells treated with PDBu + indomethacin. Conclusions. In PDBu-treated cells, there may be generation of cyclooxygenase metabolites of arachidonic acid that inhibit Na,K-ATPase activity, suppressing the stimulatory effect of PDBu on active sodium- potassium transport. Based on the observation that PGE2 can inhibit Na,K- ATPase activity and also inhibit ouabain-sensitive potassium (86Rb) uptake, the authors suggest PGE2 may influence the Na,K-ATPase response to the activation of protein kinase C in NPE cells.

Original languageEnglish (US)
Pages (from-to)866-875
Number of pages10
JournalInvestigative Ophthalmology and Visual Science
Volume38
Issue number5
StatePublished - 1997
Externally publishedYes

Fingerprint

Indomethacin
Protein Kinase C
Epithelium
Potassium
Rabbits
Dinoprostone
Ouabain
Sodium
Epithelial Cells
Immunosorbent Techniques
Masoprocol
phorbol
sodium-translocating ATPase
Lipoxygenase Inhibitors
Atomic Spectrophotometry
Cyclooxygenase Inhibitors
Phorbol Esters
Prostaglandin-Endoperoxide Synthases
Cyclic AMP
Cytochrome P-450 Enzyme System

Keywords

  • ciliary epithelium
  • eicosanoids
  • Na,K-ATPase
  • phorbol ester
  • protein kinase C

ASJC Scopus subject areas

  • Ophthalmology

Cite this

@article{54ae00496ed445f5a73f883f5a56f9dc,
title = "Indomethacin alters the Na,K-ATPase response to protein kinase C activation in cultured rabbit nonpigmented ciliary epithelium",
abstract = "Purpose. To test whether prostaglandin E2 (PGE2) is generated by cultured nonpigmented ciliary epithelial (NPE) cells treated with the phorbol ester, phorbol dibutyrate (PDBu), an activator of protein kinase C. In addition, the authors tested whether indomethacin, a cyclooxygenase inhibitor, influences the stimulation of active sodium-potassium transport observed in PDBu-treated cells. Methods. A cell line derived from rabbit NPE was used in this study. PGE2 was measured by an enzyme-linked immunosorbent assay technique. Ouabain-sensitive potassium (86Rb) uptake was measured as an index of active sodium-potassium (Na,K-ATPase-mediated) transport. Ouabain-sensitive ATP hydrolysis (Na,K-ATPase activity) also was measured. Cell sodium and potassium content was determined by atomic absorption spectrophotometry. Results. Marked PGE2 generation was observed in PDBu- treated cells. Indomethacin abolished the PGE2 response. Ouabain-sensitive potassium (86Rb) uptake was stimulated ~40{\%} in cells exposed to PDBu, but a stimulation of >100{\%} was observed in cells exposed to PDBu in the presence of indomethacin. Added alone, indomethacin did not alter ouabain-sensitive potassium (86Rb) uptake. Neither nordihydroguaiaretic acid (a lipoxygenase inhibitor) nor ethoxyresorufin (a cytochrome P450 inhibitor) altered the 86Rb uptake response to PDBu. Sodium and cyclic adenosine monophosphate content was unchanged in cells treated with PDBu + indomethacin. Conclusions. In PDBu-treated cells, there may be generation of cyclooxygenase metabolites of arachidonic acid that inhibit Na,K-ATPase activity, suppressing the stimulatory effect of PDBu on active sodium- potassium transport. Based on the observation that PGE2 can inhibit Na,K- ATPase activity and also inhibit ouabain-sensitive potassium (86Rb) uptake, the authors suggest PGE2 may influence the Na,K-ATPase response to the activation of protein kinase C in NPE cells.",
keywords = "ciliary epithelium, eicosanoids, Na,K-ATPase, phorbol ester, protein kinase C",
author = "Delamere, {Nicholas A} and James Parkerson and Yining Hou",
year = "1997",
language = "English (US)",
volume = "38",
pages = "866--875",
journal = "Investigative Ophthalmology and Visual Science",
issn = "0146-0404",
publisher = "Association for Research in Vision and Ophthalmology Inc.",
number = "5",

}

TY - JOUR

T1 - Indomethacin alters the Na,K-ATPase response to protein kinase C activation in cultured rabbit nonpigmented ciliary epithelium

AU - Delamere, Nicholas A

AU - Parkerson, James

AU - Hou, Yining

PY - 1997

Y1 - 1997

N2 - Purpose. To test whether prostaglandin E2 (PGE2) is generated by cultured nonpigmented ciliary epithelial (NPE) cells treated with the phorbol ester, phorbol dibutyrate (PDBu), an activator of protein kinase C. In addition, the authors tested whether indomethacin, a cyclooxygenase inhibitor, influences the stimulation of active sodium-potassium transport observed in PDBu-treated cells. Methods. A cell line derived from rabbit NPE was used in this study. PGE2 was measured by an enzyme-linked immunosorbent assay technique. Ouabain-sensitive potassium (86Rb) uptake was measured as an index of active sodium-potassium (Na,K-ATPase-mediated) transport. Ouabain-sensitive ATP hydrolysis (Na,K-ATPase activity) also was measured. Cell sodium and potassium content was determined by atomic absorption spectrophotometry. Results. Marked PGE2 generation was observed in PDBu- treated cells. Indomethacin abolished the PGE2 response. Ouabain-sensitive potassium (86Rb) uptake was stimulated ~40% in cells exposed to PDBu, but a stimulation of >100% was observed in cells exposed to PDBu in the presence of indomethacin. Added alone, indomethacin did not alter ouabain-sensitive potassium (86Rb) uptake. Neither nordihydroguaiaretic acid (a lipoxygenase inhibitor) nor ethoxyresorufin (a cytochrome P450 inhibitor) altered the 86Rb uptake response to PDBu. Sodium and cyclic adenosine monophosphate content was unchanged in cells treated with PDBu + indomethacin. Conclusions. In PDBu-treated cells, there may be generation of cyclooxygenase metabolites of arachidonic acid that inhibit Na,K-ATPase activity, suppressing the stimulatory effect of PDBu on active sodium- potassium transport. Based on the observation that PGE2 can inhibit Na,K- ATPase activity and also inhibit ouabain-sensitive potassium (86Rb) uptake, the authors suggest PGE2 may influence the Na,K-ATPase response to the activation of protein kinase C in NPE cells.

AB - Purpose. To test whether prostaglandin E2 (PGE2) is generated by cultured nonpigmented ciliary epithelial (NPE) cells treated with the phorbol ester, phorbol dibutyrate (PDBu), an activator of protein kinase C. In addition, the authors tested whether indomethacin, a cyclooxygenase inhibitor, influences the stimulation of active sodium-potassium transport observed in PDBu-treated cells. Methods. A cell line derived from rabbit NPE was used in this study. PGE2 was measured by an enzyme-linked immunosorbent assay technique. Ouabain-sensitive potassium (86Rb) uptake was measured as an index of active sodium-potassium (Na,K-ATPase-mediated) transport. Ouabain-sensitive ATP hydrolysis (Na,K-ATPase activity) also was measured. Cell sodium and potassium content was determined by atomic absorption spectrophotometry. Results. Marked PGE2 generation was observed in PDBu- treated cells. Indomethacin abolished the PGE2 response. Ouabain-sensitive potassium (86Rb) uptake was stimulated ~40% in cells exposed to PDBu, but a stimulation of >100% was observed in cells exposed to PDBu in the presence of indomethacin. Added alone, indomethacin did not alter ouabain-sensitive potassium (86Rb) uptake. Neither nordihydroguaiaretic acid (a lipoxygenase inhibitor) nor ethoxyresorufin (a cytochrome P450 inhibitor) altered the 86Rb uptake response to PDBu. Sodium and cyclic adenosine monophosphate content was unchanged in cells treated with PDBu + indomethacin. Conclusions. In PDBu-treated cells, there may be generation of cyclooxygenase metabolites of arachidonic acid that inhibit Na,K-ATPase activity, suppressing the stimulatory effect of PDBu on active sodium- potassium transport. Based on the observation that PGE2 can inhibit Na,K- ATPase activity and also inhibit ouabain-sensitive potassium (86Rb) uptake, the authors suggest PGE2 may influence the Na,K-ATPase response to the activation of protein kinase C in NPE cells.

KW - ciliary epithelium

KW - eicosanoids

KW - Na,K-ATPase

KW - phorbol ester

KW - protein kinase C

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M3 - Article

C2 - 9112982

AN - SCOPUS:0030950498

VL - 38

SP - 866

EP - 875

JO - Investigative Ophthalmology and Visual Science

JF - Investigative Ophthalmology and Visual Science

SN - 0146-0404

IS - 5

ER -