Endotoxin-induced cardiac depression is associated with decreased cardiac dihydropyridine receptors in rabbits

Wilbur Y.W. Lew, Satoshi Yasuda, Tony Yuan, H. Kirk Hammond

Research output: Contribution to journalArticlepeer-review

33 Citations (Scopus)

Abstract

Endotoxin depresses left ventricular (LV) contractility independently of alterations in loading conditions, acidosis, or hypoxia. We evaluated if endotoxin-induced LV depression is associated with a decrease in functional L-type calcium channels, as reflected by the number of dihydropyridine receptors measured by [3H]-PN200-110 binding. New Zealand white rabbits were instrumented with sonomicrometers to measure the end-systolic pressure-volume relationship after i.v. saline (group I, n = 6), 5 μg/kg endotoxin (group II, n = 6), or 10 μg/kg endotoxin (group III, n = 6). The end-systolic volume (ESV) measured at a matched end-systolic pressure did not change significantly over 6 h in group [(ESV changed by < 5 ± 2% S.E.) and group II (ESV changed by < 3 ± 2%), but increased markedly in group III (ESV increased 70 ± 24%, P < 0.05), indicating LV systolic depression, We measured [3H]-PN200-110 binding in crude membrane homogenates from the left ventricle. There was a dose-dependent decrease in B(max): 75 ± 5 fmol/mg protein in group I, 62 ± 3 fmol/mg in group II, and 56 ± 5 fmol/mg in group III (P = 0.02 by ANOVA). Since the majority of dihydropyridine receptors are functional L-type calcium channels in rabbits, we conclude that a decreased number of dihydropyridine receptors contributes to endotoxin-induced LV depression.

Original languageEnglish
Pages (from-to)1367-1371
Number of pages5
JournalJournal of Molecular and Cellular Cardiology
Volume28
Issue number6
DOIs
Publication statusPublished - 1996 Jun
Externally publishedYes

Keywords

  • Cardiac function
  • L-type calcium channels
  • Lipopolysaccharide
  • Sepsis

ASJC Scopus subject areas

  • Molecular Biology
  • Cardiology and Cardiovascular Medicine

Fingerprint

Dive into the research topics of 'Endotoxin-induced cardiac depression is associated with decreased cardiac dihydropyridine receptors in rabbits'. Together they form a unique fingerprint.

Cite this