Regulation of ovarian ornithine decarboxylase. Role of calcium ions in enzyme induction in isolated swine granulosa cells in vitro

Johannes D Veldhuis

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

When swine granulosa cells were cultured in chemically defined medium selectively deficient in Ca2+, the dose-dependent stimulation of ornithine decarboxylase (EC 4.1.1.17) activity in response to prostaglandin E2, l-epinephrine or the somatomedin, multiplication-stimulating activity, was attenuated markedly. Putative calcium influx blockers, verapamil and diltiazem, also inhibited hormone-stimulated enzymic activity. Similar inhibitory effects were exerted by divalent (cobalt) or trivalent (lanthanum) cations believed to compete with calcium for extracellular binding sites. The suppressive effects of extracellular calcium deprivation were time-dependent (suggesting gradual depletion of intracellular calcium stores), and could be mimicked by the intracellular antagonist of calcium action, trifluoperazine. The mechanism(s) subserving diminished hormonal induction of enzyme activity could not be accounted for by alterations in cell viability, general protein synthesis, half-life of decay of enzyme activity (measured in the presence of cycloheximide), or apparent Km of ornithine decarboxylase. Ca2+ and/or calcium antagonists did not modify enzyme activity in cell-free preparations. These observations implicate Ca2+ in the hormonal induction of a discrete cytosolic enzyme in isolated intact ovarian cells.

Original languageEnglish (US)
Pages (from-to)211-216
Number of pages6
JournalBBA - Molecular Cell Research
Volume720
Issue number2
DOIs
StatePublished - Apr 29 1982
Externally publishedYes

Fingerprint

Enzyme Induction
Ornithine Decarboxylase
Granulosa Cells
Swine
Ions
Calcium
Enzymes
Trifluoperazine
Lanthanum
Insulin-Like Growth Factor II
Diltiazem
Somatomedins
Cycloheximide
Verapamil
Cobalt
Dinoprostone
Epinephrine
Half-Life
In Vitro Techniques
Cations

Keywords

  • (Swine granulosa cell)
  • Ca
  • Enzyme induction
  • Ornithine decarboxylase

ASJC Scopus subject areas

  • Biophysics
  • Cell Biology
  • Molecular Biology
  • Medicine(all)

Cite this

Regulation of ovarian ornithine decarboxylase. Role of calcium ions in enzyme induction in isolated swine granulosa cells in vitro. / Veldhuis, Johannes D.

In: BBA - Molecular Cell Research, Vol. 720, No. 2, 29.04.1982, p. 211-216.

Research output: Contribution to journalArticle

@article{f7dabd22347e4fd1b86980eef21370fe,
title = "Regulation of ovarian ornithine decarboxylase. Role of calcium ions in enzyme induction in isolated swine granulosa cells in vitro",
abstract = "When swine granulosa cells were cultured in chemically defined medium selectively deficient in Ca2+, the dose-dependent stimulation of ornithine decarboxylase (EC 4.1.1.17) activity in response to prostaglandin E2, l-epinephrine or the somatomedin, multiplication-stimulating activity, was attenuated markedly. Putative calcium influx blockers, verapamil and diltiazem, also inhibited hormone-stimulated enzymic activity. Similar inhibitory effects were exerted by divalent (cobalt) or trivalent (lanthanum) cations believed to compete with calcium for extracellular binding sites. The suppressive effects of extracellular calcium deprivation were time-dependent (suggesting gradual depletion of intracellular calcium stores), and could be mimicked by the intracellular antagonist of calcium action, trifluoperazine. The mechanism(s) subserving diminished hormonal induction of enzyme activity could not be accounted for by alterations in cell viability, general protein synthesis, half-life of decay of enzyme activity (measured in the presence of cycloheximide), or apparent Km of ornithine decarboxylase. Ca2+ and/or calcium antagonists did not modify enzyme activity in cell-free preparations. These observations implicate Ca2+ in the hormonal induction of a discrete cytosolic enzyme in isolated intact ovarian cells.",
keywords = "(Swine granulosa cell), Ca, Enzyme induction, Ornithine decarboxylase",
author = "Veldhuis, {Johannes D}",
year = "1982",
month = "4",
day = "29",
doi = "10.1016/0167-4889(82)90014-3",
language = "English (US)",
volume = "720",
pages = "211--216",
journal = "Biochimica et Biophysica Acta - Molecular Cell Research",
issn = "0167-4889",
publisher = "Elsevier",
number = "2",

}

TY - JOUR

T1 - Regulation of ovarian ornithine decarboxylase. Role of calcium ions in enzyme induction in isolated swine granulosa cells in vitro

AU - Veldhuis, Johannes D

PY - 1982/4/29

Y1 - 1982/4/29

N2 - When swine granulosa cells were cultured in chemically defined medium selectively deficient in Ca2+, the dose-dependent stimulation of ornithine decarboxylase (EC 4.1.1.17) activity in response to prostaglandin E2, l-epinephrine or the somatomedin, multiplication-stimulating activity, was attenuated markedly. Putative calcium influx blockers, verapamil and diltiazem, also inhibited hormone-stimulated enzymic activity. Similar inhibitory effects were exerted by divalent (cobalt) or trivalent (lanthanum) cations believed to compete with calcium for extracellular binding sites. The suppressive effects of extracellular calcium deprivation were time-dependent (suggesting gradual depletion of intracellular calcium stores), and could be mimicked by the intracellular antagonist of calcium action, trifluoperazine. The mechanism(s) subserving diminished hormonal induction of enzyme activity could not be accounted for by alterations in cell viability, general protein synthesis, half-life of decay of enzyme activity (measured in the presence of cycloheximide), or apparent Km of ornithine decarboxylase. Ca2+ and/or calcium antagonists did not modify enzyme activity in cell-free preparations. These observations implicate Ca2+ in the hormonal induction of a discrete cytosolic enzyme in isolated intact ovarian cells.

AB - When swine granulosa cells were cultured in chemically defined medium selectively deficient in Ca2+, the dose-dependent stimulation of ornithine decarboxylase (EC 4.1.1.17) activity in response to prostaglandin E2, l-epinephrine or the somatomedin, multiplication-stimulating activity, was attenuated markedly. Putative calcium influx blockers, verapamil and diltiazem, also inhibited hormone-stimulated enzymic activity. Similar inhibitory effects were exerted by divalent (cobalt) or trivalent (lanthanum) cations believed to compete with calcium for extracellular binding sites. The suppressive effects of extracellular calcium deprivation were time-dependent (suggesting gradual depletion of intracellular calcium stores), and could be mimicked by the intracellular antagonist of calcium action, trifluoperazine. The mechanism(s) subserving diminished hormonal induction of enzyme activity could not be accounted for by alterations in cell viability, general protein synthesis, half-life of decay of enzyme activity (measured in the presence of cycloheximide), or apparent Km of ornithine decarboxylase. Ca2+ and/or calcium antagonists did not modify enzyme activity in cell-free preparations. These observations implicate Ca2+ in the hormonal induction of a discrete cytosolic enzyme in isolated intact ovarian cells.

KW - (Swine granulosa cell)

KW - Ca

KW - Enzyme induction

KW - Ornithine decarboxylase

UR - http://www.scopus.com/inward/record.url?scp=0020493185&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0020493185&partnerID=8YFLogxK

U2 - 10.1016/0167-4889(82)90014-3

DO - 10.1016/0167-4889(82)90014-3

M3 - Article

C2 - 6952940

AN - SCOPUS:0020493185

VL - 720

SP - 211

EP - 216

JO - Biochimica et Biophysica Acta - Molecular Cell Research

JF - Biochimica et Biophysica Acta - Molecular Cell Research

SN - 0167-4889

IS - 2

ER -