Role of intracellular calcium in peroxide-induced potentiation of norepinephrine release from bovine isolated irides

Gen Pharmacol. 1998 Nov;31(5):793-8. doi: 10.1016/s0306-3623(98)00090-1.

Abstract

1. BAPTA AM (10 microM), thapsigargin (10 microM), ruthenium red (30 microM) and oligomycin (30 microM) inhibited field-stimulated [3H]NE release from bovine isolated irides by 54%, 30%, 30% and 26%, respectively. 2. Both BAPTA AM and thapsigargin had no significant effect (P>0.05) on H2O2-induced potentiation of evoked [3H]NE release. 3. Ruthenium red prevented (but oligomycin enhanced) H2O2-induced enhancement of evoked [3H]NE release. 4. We conclude that, although intracellular calcium participates in field-stimulation evoked [3H]NE release from bovine isolated irides, only the mitochondrial pool of calcium may be involved in peroxide-induced enhancement of sympathetic neurotransmission.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Calcium / antagonists & inhibitors
  • Calcium / metabolism*
  • Calcium-Transporting ATPases / antagonists & inhibitors
  • Cattle
  • Chelating Agents / pharmacology
  • Drug Synergism
  • Egtazic Acid / analogs & derivatives
  • Egtazic Acid / pharmacology
  • Electric Stimulation
  • Enzyme Inhibitors / pharmacology
  • Homeostasis
  • Hydrogen Peroxide / pharmacology*
  • In Vitro Techniques
  • Intracellular Fluid / drug effects
  • Intracellular Fluid / metabolism*
  • Iris / drug effects*
  • Iris / metabolism
  • Iris / ultrastructure
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • Norepinephrine / metabolism*
  • Oligomycins / pharmacology
  • Ruthenium Red / pharmacology
  • Thapsigargin / pharmacology

Substances

  • Chelating Agents
  • Enzyme Inhibitors
  • Oligomycins
  • Ruthenium Red
  • Egtazic Acid
  • Thapsigargin
  • Hydrogen Peroxide
  • Calcium-Transporting ATPases
  • 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid
  • Calcium
  • Norepinephrine