Calcium oscillations index the extent of calcium loading and predict functional recovery during reperfusion in rat myocardium

Research output: Contribution to journalArticle

Abstract

Delayed recovery of contractile function after myocardial ischemia may be due to prolonged recovery of high-energy phosphates, persistent acidosis, increased inorganic phosphate, and/or calcium loading. To examine these potential mechanisms, metabolic parameters measured by 31P nuclear magnetic resonance spectroscopy, and spontaneous diastolic myofilament motion caused by sarcoplasmic reticulum-myofilament calcium cycling indexed by the scattered light intensity fluctuations (SLIF) it produces in laser beam reflected from the heart, were studied in isolated atrioventricularly blocked rat hearts (n = 10) after 65 min of ischemia at 30°C. All metabolic parameters recovered to their full extent 5 min after reperfusion. Developed pressure evidenced a small recovery but then fell abruptly. This was accompanied by an increase in end diastolic pressure to 37±5 mm Hg and a fourfold increase in SLIF, to 252±58% of baseline. In another series of hearts initial reperfusion with calcium of 0.08 mM prevented the SLIF rise and resulted in improved developed pressure (74±3% vs. 39±13% of control), and lower cell calcium (5.9±3 vs. 10.3±1.4 μmol/g dry wt). Thus, during reperfusion, delayed contractile recovery is not associated with delayed recovery of pH, inorganic phosphate, or high-energy phosphates and can be attributed, in part, to an adverse effect of calcium loading which can be indexed by increased SLIF occurring at that time.

Original languageEnglish (US)
Pages (from-to)757-765
Number of pages9
JournalJournal of Clinical Investigation
Volume85
Issue number3
StatePublished - Mar 1990
Externally publishedYes

Fingerprint

Calcium Signaling
Reperfusion
Myocardium
Calcium
Phosphates
Light
Myofibrils
Pressure
Recovery of Function
Sarcoplasmic Reticulum
Acidosis
Myocardial Ischemia
Lasers
Magnetic Resonance Spectroscopy
Ischemia
Blood Pressure

Keywords

  • Diastolic calcium oscillations
  • High-energy phosphates
  • Reperfusion

ASJC Scopus subject areas

  • Medicine(all)

Cite this

@article{dcb3dd5373f541fdaf914f79be17f768,
title = "Calcium oscillations index the extent of calcium loading and predict functional recovery during reperfusion in rat myocardium",
abstract = "Delayed recovery of contractile function after myocardial ischemia may be due to prolonged recovery of high-energy phosphates, persistent acidosis, increased inorganic phosphate, and/or calcium loading. To examine these potential mechanisms, metabolic parameters measured by 31P nuclear magnetic resonance spectroscopy, and spontaneous diastolic myofilament motion caused by sarcoplasmic reticulum-myofilament calcium cycling indexed by the scattered light intensity fluctuations (SLIF) it produces in laser beam reflected from the heart, were studied in isolated atrioventricularly blocked rat hearts (n = 10) after 65 min of ischemia at 30°C. All metabolic parameters recovered to their full extent 5 min after reperfusion. Developed pressure evidenced a small recovery but then fell abruptly. This was accompanied by an increase in end diastolic pressure to 37±5 mm Hg and a fourfold increase in SLIF, to 252±58{\%} of baseline. In another series of hearts initial reperfusion with calcium of 0.08 mM prevented the SLIF rise and resulted in improved developed pressure (74±3{\%} vs. 39±13{\%} of control), and lower cell calcium (5.9±3 vs. 10.3±1.4 μmol/g dry wt). Thus, during reperfusion, delayed contractile recovery is not associated with delayed recovery of pH, inorganic phosphate, or high-energy phosphates and can be attributed, in part, to an adverse effect of calcium loading which can be indexed by increased SLIF occurring at that time.",
keywords = "Diastolic calcium oscillations, High-energy phosphates, Reperfusion",
author = "Weiss, {Robert George} and Gary Gerstenblith and Edward Lakatta",
year = "1990",
month = "3",
language = "English (US)",
volume = "85",
pages = "757--765",
journal = "Journal of Clinical Investigation",
issn = "0021-9738",
publisher = "The American Society for Clinical Investigation",
number = "3",

}

TY - JOUR

T1 - Calcium oscillations index the extent of calcium loading and predict functional recovery during reperfusion in rat myocardium

AU - Weiss, Robert George

AU - Gerstenblith, Gary

AU - Lakatta, Edward

PY - 1990/3

Y1 - 1990/3

N2 - Delayed recovery of contractile function after myocardial ischemia may be due to prolonged recovery of high-energy phosphates, persistent acidosis, increased inorganic phosphate, and/or calcium loading. To examine these potential mechanisms, metabolic parameters measured by 31P nuclear magnetic resonance spectroscopy, and spontaneous diastolic myofilament motion caused by sarcoplasmic reticulum-myofilament calcium cycling indexed by the scattered light intensity fluctuations (SLIF) it produces in laser beam reflected from the heart, were studied in isolated atrioventricularly blocked rat hearts (n = 10) after 65 min of ischemia at 30°C. All metabolic parameters recovered to their full extent 5 min after reperfusion. Developed pressure evidenced a small recovery but then fell abruptly. This was accompanied by an increase in end diastolic pressure to 37±5 mm Hg and a fourfold increase in SLIF, to 252±58% of baseline. In another series of hearts initial reperfusion with calcium of 0.08 mM prevented the SLIF rise and resulted in improved developed pressure (74±3% vs. 39±13% of control), and lower cell calcium (5.9±3 vs. 10.3±1.4 μmol/g dry wt). Thus, during reperfusion, delayed contractile recovery is not associated with delayed recovery of pH, inorganic phosphate, or high-energy phosphates and can be attributed, in part, to an adverse effect of calcium loading which can be indexed by increased SLIF occurring at that time.

AB - Delayed recovery of contractile function after myocardial ischemia may be due to prolonged recovery of high-energy phosphates, persistent acidosis, increased inorganic phosphate, and/or calcium loading. To examine these potential mechanisms, metabolic parameters measured by 31P nuclear magnetic resonance spectroscopy, and spontaneous diastolic myofilament motion caused by sarcoplasmic reticulum-myofilament calcium cycling indexed by the scattered light intensity fluctuations (SLIF) it produces in laser beam reflected from the heart, were studied in isolated atrioventricularly blocked rat hearts (n = 10) after 65 min of ischemia at 30°C. All metabolic parameters recovered to their full extent 5 min after reperfusion. Developed pressure evidenced a small recovery but then fell abruptly. This was accompanied by an increase in end diastolic pressure to 37±5 mm Hg and a fourfold increase in SLIF, to 252±58% of baseline. In another series of hearts initial reperfusion with calcium of 0.08 mM prevented the SLIF rise and resulted in improved developed pressure (74±3% vs. 39±13% of control), and lower cell calcium (5.9±3 vs. 10.3±1.4 μmol/g dry wt). Thus, during reperfusion, delayed contractile recovery is not associated with delayed recovery of pH, inorganic phosphate, or high-energy phosphates and can be attributed, in part, to an adverse effect of calcium loading which can be indexed by increased SLIF occurring at that time.

KW - Diastolic calcium oscillations

KW - High-energy phosphates

KW - Reperfusion

UR - http://www.scopus.com/inward/record.url?scp=0025217952&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025217952&partnerID=8YFLogxK

M3 - Article

C2 - 2312726

AN - SCOPUS:0025217952

VL - 85

SP - 757

EP - 765

JO - Journal of Clinical Investigation

JF - Journal of Clinical Investigation

SN - 0021-9738

IS - 3

ER -