Tags

Type your tag names separated by a space and hit enter

Chronic infarction decreases maximum cardiac work and sensitivity of heart to extracellular calcium.
Am J Physiol. 1985 Jul; 249(1 Pt 2):H80-7.AJ

Abstract

Rat hearts were infarcted in vivo by ligation of the left ventricular coronary artery to cause an initial 40% loss of viable tissue by weight. Due to compensatory hypertrophy of the surviving myocardium and progression of the infarct to scar tissue, the infarct represented approximately 25% by weight of the whole heart after 1 wk. After 1 or 3 wk, these infarcted hearts were removed and perfused in vitro by the working hearts technique. Ventricular pressure development and positive dP/dt were lower in infarcted hearts compared with sham-operated ones. O2 consumption and glucose utilization by viable tissue per unit pressure development was the same in normal and infarcted hearts. Levels of creatine phosphate and free creatine were decreased, but ATP and total adenine nucleotides were well maintained. The inotropic response to decreases in extracellular [Ca2+] was much greater in infarcted hearts than in sham controls. Prenalterol increased ventricular function proportionally more in infarcted than in the sham-operated hearts, suggesting that down regulation of beta receptors was not a problem. The infarcted hearts were much more sensitive to verapamil than control hearts. It is concluded that the depressed function of the noninfarcted tissue of chronically infarcted hearts is due in part to loss of functioning tissue mass and in part to decreased sensitivity to extracellular Ca2+.

Authors

No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.

Language

eng

PubMed ID

2861751

Citation

Fellenius, E, et al. "Chronic Infarction Decreases Maximum Cardiac Work and Sensitivity of Heart to Extracellular Calcium." The American Journal of Physiology, vol. 249, no. 1 Pt 2, 1985, pp. H80-7.
Fellenius E, Hansen CA, Mjøs O, et al. Chronic infarction decreases maximum cardiac work and sensitivity of heart to extracellular calcium. Am J Physiol. 1985;249(1 Pt 2):H80-7.
Fellenius, E., Hansen, C. A., Mjøs, O., & Neely, J. R. (1985). Chronic infarction decreases maximum cardiac work and sensitivity of heart to extracellular calcium. The American Journal of Physiology, 249(1 Pt 2), H80-7.
Fellenius E, et al. Chronic Infarction Decreases Maximum Cardiac Work and Sensitivity of Heart to Extracellular Calcium. Am J Physiol. 1985;249(1 Pt 2):H80-7. PubMed PMID: 2861751.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Chronic infarction decreases maximum cardiac work and sensitivity of heart to extracellular calcium. AU - Fellenius,E, AU - Hansen,C A, AU - Mjøs,O, AU - Neely,J R, PY - 1985/7/1/pubmed PY - 1985/7/1/medline PY - 1985/7/1/entrez SP - H80 EP - 7 JF - The American journal of physiology JO - Am J Physiol VL - 249 IS - 1 Pt 2 N2 - Rat hearts were infarcted in vivo by ligation of the left ventricular coronary artery to cause an initial 40% loss of viable tissue by weight. Due to compensatory hypertrophy of the surviving myocardium and progression of the infarct to scar tissue, the infarct represented approximately 25% by weight of the whole heart after 1 wk. After 1 or 3 wk, these infarcted hearts were removed and perfused in vitro by the working hearts technique. Ventricular pressure development and positive dP/dt were lower in infarcted hearts compared with sham-operated ones. O2 consumption and glucose utilization by viable tissue per unit pressure development was the same in normal and infarcted hearts. Levels of creatine phosphate and free creatine were decreased, but ATP and total adenine nucleotides were well maintained. The inotropic response to decreases in extracellular [Ca2+] was much greater in infarcted hearts than in sham controls. Prenalterol increased ventricular function proportionally more in infarcted than in the sham-operated hearts, suggesting that down regulation of beta receptors was not a problem. The infarcted hearts were much more sensitive to verapamil than control hearts. It is concluded that the depressed function of the noninfarcted tissue of chronically infarcted hearts is due in part to loss of functioning tissue mass and in part to decreased sensitivity to extracellular Ca2+. SN - 0002-9513 UR - https://www.unboundmedicine.com/medline/citation/2861751/Chronic_infarction_decreases_maximum_cardiac_work_and_sensitivity_of_heart_to_extracellular_calcium_ L2 - https://journals.physiology.org/doi/10.1152/ajpheart.1985.249.1.H80?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub=pubmed DB - PRIME DP - Unbound Medicine ER -