beta-Adrenergic agonist-induced nitrite production in isolated pig ciliary processes

Graefes Arch Clin Exp Ophthalmol. 1998 Aug;236(8):613-6. doi: 10.1007/s004170050130.

Abstract

Background: We performed an experiment to assess whether in ciliary processes adrenergic-receptor agents can modulate the production of nitrite, an oxidized metabolite of nitric oxide (NO).

Methods: The porcine ciliary processes and the iris were dissected and stored at -20 degrees C. Later, tissues were thawed, and nitrite measured by Griess reaction, before and 2 h after exposure to various drugs.

Results: In the ciliary processes, but not in the iris, the alpha-, beta-adrenergic receptor agonist, norepinephrine (0.01-10 microM), increased nitrite production (95 +/- 12%, P < 0.01). The norepinephrine-induced (0.1 microM) nitrite production was inhibited by the inhibitor of NO synthase, N omega-nitro-L-arginine methyl ester (0.5 mM; P < 0.05) and by the non-selective beta-adrenergic receptor antagonist, propranolol (10 microM; P < 0.01), but not by the non-selective alpha-adrenergic receptor antagonist, phentolamine (10 microM).

Conclusion: In isolated porcine ciliary processes, beta-adrenergic receptor stimulation increases NO production.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenergic beta-Agonists / pharmacology*
  • Adrenergic beta-Antagonists / pharmacology
  • Animals
  • Ciliary Body / drug effects*
  • Ciliary Body / metabolism
  • Enzyme Inhibitors / pharmacology
  • NG-Nitroarginine Methyl Ester / pharmacology
  • Nitric Oxide / biosynthesis
  • Nitric Oxide Synthase / antagonists & inhibitors
  • Nitrites / metabolism*
  • Norepinephrine / antagonists & inhibitors
  • Norepinephrine / pharmacology*
  • Propranolol / pharmacology
  • Receptors, Adrenergic, beta / metabolism*
  • Swine

Substances

  • Adrenergic beta-Agonists
  • Adrenergic beta-Antagonists
  • Enzyme Inhibitors
  • Nitrites
  • Receptors, Adrenergic, beta
  • Nitric Oxide
  • Propranolol
  • Nitric Oxide Synthase
  • NG-Nitroarginine Methyl Ester
  • Norepinephrine