Role of eicosanoids in vasopressin-induced calcium mobilization in A7r5 vascular smooth muscle cells

M. Thibonnier, A. L. Bayer, C. L. Laethem, Dennis Koop, M. S. Simonson

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

The role of arachidonic acid (AA) and its metabolites in vasopressin (AVP)-induced calcium mobilization in A7r5 aortic smooth muscle cells was explored by intracellular calcium monitoring, [14C]AA labeling, and high- performance liquid chromatography (HPLC) techniques. In fura 2-loaded A7r5 cells, AA potentiated AVP-stimulated increase in intracellular free Ca2+ ([Ca2+](i)). The cyclooxygenase inhibitor indomethacin reduced both the AA- and AVP-induced influx of extracellular Ca2+. AVP-induced [Ca2+](i) transients were not altered by lipoxygenase inhibitors but were reduced in a dose-dependent fashion by ketoconazole, an inhibitor of cytochrome P-450 monooxygenases. Among several epoxygenase metabolites of AA tested, 5,6- epoxyeicosatrienoic acid potentiated AVP-induced [Ca2+](i) transients. Reverse-phase HPLC analysis of lipid extracts from A7r5 cells prelabeled with [14C]AA isolated a radioactive peak that did not coelute with established products of cyclooxygenase-, lipoxygenase-, or cytochrome P-450-catalyzed oxidations of AA. This peak was significantly increased after AVP stimulation and was completely blocked by preincubation with ketoconazole. Thus the stimulation of V1-vascular AVP receptors of A7r5 cells triggers several cytoplasmic signaling pathways involving AA metabolite formation through the cyclooxygenase and epoxygenase pathways.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Endocrinology and Metabolism
Volume265
Issue number1 28-1
StatePublished - 1993
Externally publishedYes

Fingerprint

Eicosanoids
Vasopressins
Vascular Smooth Muscle
Arachidonic Acid
Smooth Muscle Myocytes
Muscle
Cells
Calcium
Metabolites
Ketoconazole
Prostaglandin-Endoperoxide Synthases
High performance liquid chromatography
High Pressure Liquid Chromatography
Lipoxygenase Inhibitors
Lipoxygenase
Cyclooxygenase Inhibitors
Fura-2
Reverse-Phase Chromatography
Cell Extracts
Indomethacin

Keywords

  • arachidonic acid metabolites
  • calcium fluxes
  • vasopressin receptors

ASJC Scopus subject areas

  • Biochemistry
  • Endocrinology
  • Physiology

Cite this

Role of eicosanoids in vasopressin-induced calcium mobilization in A7r5 vascular smooth muscle cells. / Thibonnier, M.; Bayer, A. L.; Laethem, C. L.; Koop, Dennis; Simonson, M. S.

In: American Journal of Physiology - Endocrinology and Metabolism, Vol. 265, No. 1 28-1, 1993.

Research output: Contribution to journalArticle

@article{27ddf99ef997405083628131ad8c388b,
title = "Role of eicosanoids in vasopressin-induced calcium mobilization in A7r5 vascular smooth muscle cells",
abstract = "The role of arachidonic acid (AA) and its metabolites in vasopressin (AVP)-induced calcium mobilization in A7r5 aortic smooth muscle cells was explored by intracellular calcium monitoring, [14C]AA labeling, and high- performance liquid chromatography (HPLC) techniques. In fura 2-loaded A7r5 cells, AA potentiated AVP-stimulated increase in intracellular free Ca2+ ([Ca2+](i)). The cyclooxygenase inhibitor indomethacin reduced both the AA- and AVP-induced influx of extracellular Ca2+. AVP-induced [Ca2+](i) transients were not altered by lipoxygenase inhibitors but were reduced in a dose-dependent fashion by ketoconazole, an inhibitor of cytochrome P-450 monooxygenases. Among several epoxygenase metabolites of AA tested, 5,6- epoxyeicosatrienoic acid potentiated AVP-induced [Ca2+](i) transients. Reverse-phase HPLC analysis of lipid extracts from A7r5 cells prelabeled with [14C]AA isolated a radioactive peak that did not coelute with established products of cyclooxygenase-, lipoxygenase-, or cytochrome P-450-catalyzed oxidations of AA. This peak was significantly increased after AVP stimulation and was completely blocked by preincubation with ketoconazole. Thus the stimulation of V1-vascular AVP receptors of A7r5 cells triggers several cytoplasmic signaling pathways involving AA metabolite formation through the cyclooxygenase and epoxygenase pathways.",
keywords = "arachidonic acid metabolites, calcium fluxes, vasopressin receptors",
author = "M. Thibonnier and Bayer, {A. L.} and Laethem, {C. L.} and Dennis Koop and Simonson, {M. S.}",
year = "1993",
language = "English (US)",
volume = "265",
journal = "American Journal of Physiology - Renal Fluid and Electrolyte Physiology",
issn = "1931-857X",
publisher = "American Physiological Society",
number = "1 28-1",

}

TY - JOUR

T1 - Role of eicosanoids in vasopressin-induced calcium mobilization in A7r5 vascular smooth muscle cells

AU - Thibonnier, M.

AU - Bayer, A. L.

AU - Laethem, C. L.

AU - Koop, Dennis

AU - Simonson, M. S.

PY - 1993

Y1 - 1993

N2 - The role of arachidonic acid (AA) and its metabolites in vasopressin (AVP)-induced calcium mobilization in A7r5 aortic smooth muscle cells was explored by intracellular calcium monitoring, [14C]AA labeling, and high- performance liquid chromatography (HPLC) techniques. In fura 2-loaded A7r5 cells, AA potentiated AVP-stimulated increase in intracellular free Ca2+ ([Ca2+](i)). The cyclooxygenase inhibitor indomethacin reduced both the AA- and AVP-induced influx of extracellular Ca2+. AVP-induced [Ca2+](i) transients were not altered by lipoxygenase inhibitors but were reduced in a dose-dependent fashion by ketoconazole, an inhibitor of cytochrome P-450 monooxygenases. Among several epoxygenase metabolites of AA tested, 5,6- epoxyeicosatrienoic acid potentiated AVP-induced [Ca2+](i) transients. Reverse-phase HPLC analysis of lipid extracts from A7r5 cells prelabeled with [14C]AA isolated a radioactive peak that did not coelute with established products of cyclooxygenase-, lipoxygenase-, or cytochrome P-450-catalyzed oxidations of AA. This peak was significantly increased after AVP stimulation and was completely blocked by preincubation with ketoconazole. Thus the stimulation of V1-vascular AVP receptors of A7r5 cells triggers several cytoplasmic signaling pathways involving AA metabolite formation through the cyclooxygenase and epoxygenase pathways.

AB - The role of arachidonic acid (AA) and its metabolites in vasopressin (AVP)-induced calcium mobilization in A7r5 aortic smooth muscle cells was explored by intracellular calcium monitoring, [14C]AA labeling, and high- performance liquid chromatography (HPLC) techniques. In fura 2-loaded A7r5 cells, AA potentiated AVP-stimulated increase in intracellular free Ca2+ ([Ca2+](i)). The cyclooxygenase inhibitor indomethacin reduced both the AA- and AVP-induced influx of extracellular Ca2+. AVP-induced [Ca2+](i) transients were not altered by lipoxygenase inhibitors but were reduced in a dose-dependent fashion by ketoconazole, an inhibitor of cytochrome P-450 monooxygenases. Among several epoxygenase metabolites of AA tested, 5,6- epoxyeicosatrienoic acid potentiated AVP-induced [Ca2+](i) transients. Reverse-phase HPLC analysis of lipid extracts from A7r5 cells prelabeled with [14C]AA isolated a radioactive peak that did not coelute with established products of cyclooxygenase-, lipoxygenase-, or cytochrome P-450-catalyzed oxidations of AA. This peak was significantly increased after AVP stimulation and was completely blocked by preincubation with ketoconazole. Thus the stimulation of V1-vascular AVP receptors of A7r5 cells triggers several cytoplasmic signaling pathways involving AA metabolite formation through the cyclooxygenase and epoxygenase pathways.

KW - arachidonic acid metabolites

KW - calcium fluxes

KW - vasopressin receptors

UR - http://www.scopus.com/inward/record.url?scp=0027284161&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027284161&partnerID=8YFLogxK

M3 - Article

VL - 265

JO - American Journal of Physiology - Renal Fluid and Electrolyte Physiology

JF - American Journal of Physiology - Renal Fluid and Electrolyte Physiology

SN - 1931-857X

IS - 1 28-1

ER -