The action of oxidized low density lipoprotein on calcium transients in isolated rabbit cardiomyocytes

K. Liu, Hamid Massaeli, G. N. Pierce

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

The effect of oxidized low density lipoprotein (oxLDL) on the Ca2+ transients of isolated rabbit cardiomyocytes was assessed. LDL was oxidized by a free radical generating system in vitro. The systolic Ca2+ concentration in transients was significantly increased after treatment with 100 μg of oxLDL cholesterol/ml for 16 min without having any effect on the diastolic [Ca2+]. However, a toxic effect was observed when the concentration of oxLDL was increased to 1,000 μg/ml. Cells treated with 100 μg of oxLDL/ml were more sensitive to the blocking action of nicardipine on the Ca2+ transient than were control cardiomyocytes. Furthermore, oxLDL failed to produce a stimulatory effect on the transient when the extracellular [Ca2+] was lowered. The malondialdehyde content in the oxLDL correlated well with the change in systolic [Ca2+] of treated cells. Lazaroid, a novel antioxidant, completely inhibited malondialdehyde formation in the oxLDL and prevented the increment of systolic [Ca2+] in the treated cells. The data indicate that oxLDL can induce relatively rapid alterations in cellular Ca2+ transients via a modification of Ca2+ entry through the L-type Ca2+ channel. LDL oxidation induced by free radicals may play an important role in influencing cardiac contractile function during pathological conditions such as ischemia/reperfusion challenge.

Original languageEnglish
Pages (from-to)4145-4151
Number of pages7
JournalJournal of Biological Chemistry
Volume268
Issue number6
Publication statusPublished - 9 Mar 1993
Externally publishedYes

    Fingerprint

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Cite this