Effect of lysophosphatidylcholine on vasomotor functions of porcine coronary arteries

J Surg Res. 2005 Jun 15;126(2):182-8. doi: 10.1016/j.jss.2005.01.015.

Abstract

Background: Lysophosphatidylcholine (LPC) is a product of phosphatidylcholine hydrolysis by phospholipase A(2) and a mediator of the lipid-induced atherosclerotic changes. In this study, we determined the effects of LPC on vasomotor functions, oxidative stress, and endothelial nitric oxide synthase (eNOS) expression in porcine coronary arteries.

Methods: Porcine coronary arteries were cut into 5-mm rings and were treated with LPC or antioxidant selenomethionine (SeMet). For the vasomotor studies, we used a myograph tension system. Levels of superoxide anion (O(2)(-)) were detected by the lucigenin-enhanced chemiluminescence method. The eNOS protein level was studied by immunohistochemistry with avidin-biotin complex immunoperoxidase procedure.

Results: Endothelium-dependent relaxation in response to bradykinin was reduced by 36% and 81% for the rings treated with 12.5 and 25 mum of LPC, respectively, as compared with controls (P < 0.05). Endothelium-independent relaxation in response to sodium nitroprusside also was reduced by 63% after treatment with 25 mum LPC (P < 0.05). The O(2)(-) level was increased in the porcine arteries treated with 25 mum of LPC by 41% as compared with controls (P < 0.05). The antioxidant SeMet reversed the effects of LPC on vascular relaxation and O(2)(-) production. Immunoreactivity of eNOS in LPC-treated vessel rings also was reduced substantially.

Conclusions: LPC impairs endothelium-dependent and endothelium-independent vasorelaxation. This effect is associated with increased superoxide radical production and decreased eNOS activity and is practically reversed with the use of the antioxidant SeMet.

Publication types

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

MeSH terms

  • Animals
  • Antioxidants / pharmacology
  • Coronary Vessels / metabolism
  • Coronary Vessels / physiology*
  • Dose-Response Relationship, Drug
  • Immunohistochemistry
  • In Vitro Techniques
  • Lysophosphatidylcholines / administration & dosage
  • Lysophosphatidylcholines / pharmacology*
  • Nitric Oxide Synthase / antagonists & inhibitors
  • Nitric Oxide Synthase Type III
  • Oxidative Stress
  • Selenomethionine / pharmacology
  • Superoxides / metabolism
  • Swine
  • Vasodilation / drug effects
  • Vasomotor System / drug effects*

Substances

  • Antioxidants
  • Lysophosphatidylcholines
  • Superoxides
  • Selenomethionine
  • Nitric Oxide Synthase
  • Nitric Oxide Synthase Type III