In vitro myocardial performance after lethal and nonlethal doses of endotoxin

K. H. McDonough, B. A. Brumfield, C. H. Lang

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

The present study was initiated to determine whether the myocardial effects of an in vivo injection of endotoxin into rats were correlated with the dose and thus the lethality of the endotoxin administered. All animals in this study were used 4 h after a bolus injection of 1,000, 100, 10, or 1 μg/100 g body wt of Escherichia coli endotoxin. At this time, mean arterial blood pressure had returned to control levels but cardiac output was still depressed at the three higher doses as previously reported. Intrinsic function of the myocardium was assessed using the isolated perfused working heart preparation. Cardiac output and pressure development were measured at varying preloads and at two levels of aortic outflow resistance. In vitro approaches were chosen for this study to eliminate peripheral vascular changes and humoral or neural alterations that might influence myocardial performance in vivo. Results indicate that coronary vascular resistance was increased in all hearts from endotoxin-treated animals compared with controls. In addition, myocardial performance was impaired at several doses of endotoxin, and the degree of dysfunction was dependent on the dose of endotoxin administered. Dysfunction, i.e., a depression in cardiac output times peak systolic pressure, was evident at the two higher doses in which there was 50 and 10% lethality by 24 h and also in the lower dose of 10 μg/100 g, which was nonlethal. Cardiac output appeared to be very sensitive to the consequences of endotoxin administration. Defects in myocardial performance could be revealed by increasing preload or afterload stress on the hearts. Thus myocardial reserve is compromised by in vivo endotoxin administration in a dose-dependent fashion.

Original languageEnglish (US)
Pages (from-to)19/2
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume250
Issue number2
StatePublished - Jan 1 1986

Fingerprint

Endotoxins
Cardiac Output
Arterial Pressure
Injections
In Vitro Techniques
Vascular Resistance
Blood Vessels
Myocardium
Blood Pressure
Pressure

All Science Journal Classification (ASJC) codes

  • Physiology
  • Cardiology and Cardiovascular Medicine
  • Physiology (medical)

Cite this

@article{64a243a90adf4dd382d739ca81f80e0d,
title = "In vitro myocardial performance after lethal and nonlethal doses of endotoxin",
abstract = "The present study was initiated to determine whether the myocardial effects of an in vivo injection of endotoxin into rats were correlated with the dose and thus the lethality of the endotoxin administered. All animals in this study were used 4 h after a bolus injection of 1,000, 100, 10, or 1 μg/100 g body wt of Escherichia coli endotoxin. At this time, mean arterial blood pressure had returned to control levels but cardiac output was still depressed at the three higher doses as previously reported. Intrinsic function of the myocardium was assessed using the isolated perfused working heart preparation. Cardiac output and pressure development were measured at varying preloads and at two levels of aortic outflow resistance. In vitro approaches were chosen for this study to eliminate peripheral vascular changes and humoral or neural alterations that might influence myocardial performance in vivo. Results indicate that coronary vascular resistance was increased in all hearts from endotoxin-treated animals compared with controls. In addition, myocardial performance was impaired at several doses of endotoxin, and the degree of dysfunction was dependent on the dose of endotoxin administered. Dysfunction, i.e., a depression in cardiac output times peak systolic pressure, was evident at the two higher doses in which there was 50 and 10{\%} lethality by 24 h and also in the lower dose of 10 μg/100 g, which was nonlethal. Cardiac output appeared to be very sensitive to the consequences of endotoxin administration. Defects in myocardial performance could be revealed by increasing preload or afterload stress on the hearts. Thus myocardial reserve is compromised by in vivo endotoxin administration in a dose-dependent fashion.",
author = "McDonough, {K. H.} and Brumfield, {B. A.} and Lang, {C. H.}",
year = "1986",
month = "1",
day = "1",
language = "English (US)",
volume = "250",
pages = "19/2",
journal = "American Journal of Physiology",
issn = "0363-6135",
publisher = "American Physiological Society",
number = "2",

}

In vitro myocardial performance after lethal and nonlethal doses of endotoxin. / McDonough, K. H.; Brumfield, B. A.; Lang, C. H.

In: American Journal of Physiology - Heart and Circulatory Physiology, Vol. 250, No. 2, 01.01.1986, p. 19/2.

Research output: Contribution to journalArticle

TY - JOUR

T1 - In vitro myocardial performance after lethal and nonlethal doses of endotoxin

AU - McDonough, K. H.

AU - Brumfield, B. A.

AU - Lang, C. H.

PY - 1986/1/1

Y1 - 1986/1/1

N2 - The present study was initiated to determine whether the myocardial effects of an in vivo injection of endotoxin into rats were correlated with the dose and thus the lethality of the endotoxin administered. All animals in this study were used 4 h after a bolus injection of 1,000, 100, 10, or 1 μg/100 g body wt of Escherichia coli endotoxin. At this time, mean arterial blood pressure had returned to control levels but cardiac output was still depressed at the three higher doses as previously reported. Intrinsic function of the myocardium was assessed using the isolated perfused working heart preparation. Cardiac output and pressure development were measured at varying preloads and at two levels of aortic outflow resistance. In vitro approaches were chosen for this study to eliminate peripheral vascular changes and humoral or neural alterations that might influence myocardial performance in vivo. Results indicate that coronary vascular resistance was increased in all hearts from endotoxin-treated animals compared with controls. In addition, myocardial performance was impaired at several doses of endotoxin, and the degree of dysfunction was dependent on the dose of endotoxin administered. Dysfunction, i.e., a depression in cardiac output times peak systolic pressure, was evident at the two higher doses in which there was 50 and 10% lethality by 24 h and also in the lower dose of 10 μg/100 g, which was nonlethal. Cardiac output appeared to be very sensitive to the consequences of endotoxin administration. Defects in myocardial performance could be revealed by increasing preload or afterload stress on the hearts. Thus myocardial reserve is compromised by in vivo endotoxin administration in a dose-dependent fashion.

AB - The present study was initiated to determine whether the myocardial effects of an in vivo injection of endotoxin into rats were correlated with the dose and thus the lethality of the endotoxin administered. All animals in this study were used 4 h after a bolus injection of 1,000, 100, 10, or 1 μg/100 g body wt of Escherichia coli endotoxin. At this time, mean arterial blood pressure had returned to control levels but cardiac output was still depressed at the three higher doses as previously reported. Intrinsic function of the myocardium was assessed using the isolated perfused working heart preparation. Cardiac output and pressure development were measured at varying preloads and at two levels of aortic outflow resistance. In vitro approaches were chosen for this study to eliminate peripheral vascular changes and humoral or neural alterations that might influence myocardial performance in vivo. Results indicate that coronary vascular resistance was increased in all hearts from endotoxin-treated animals compared with controls. In addition, myocardial performance was impaired at several doses of endotoxin, and the degree of dysfunction was dependent on the dose of endotoxin administered. Dysfunction, i.e., a depression in cardiac output times peak systolic pressure, was evident at the two higher doses in which there was 50 and 10% lethality by 24 h and also in the lower dose of 10 μg/100 g, which was nonlethal. Cardiac output appeared to be very sensitive to the consequences of endotoxin administration. Defects in myocardial performance could be revealed by increasing preload or afterload stress on the hearts. Thus myocardial reserve is compromised by in vivo endotoxin administration in a dose-dependent fashion.

UR - http://www.scopus.com/inward/record.url?scp=0022495783&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0022495783&partnerID=8YFLogxK

M3 - Article

C2 - 3946624

AN - SCOPUS:0022495783

VL - 250

SP - 19/2

JO - American Journal of Physiology

JF - American Journal of Physiology

SN - 0363-6135

IS - 2

ER -