Aging Effects on Myocardial Hypertrophic Response and Coronary Circulation in Pressure-Overload

Shogen Isoyama, Masao Kuroha, Fumitoshi Sato, Nobuhiko Ito, Tamotsu Takishima, Shogen Isoyama

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)

Abstract

We examined the effect of age on capacity for myocardial hypertrophy, pressure-generating abihty and coronary circulation after imposition of pressure-overload. Marked right ventricular and cellular hypertrophy was observed 1 week after pulmonary artery constriction in the developmental phase of rats (2 months of age) and after 3 weeks in the young-adult rats (7 months). In old rats (18 months) similar increases in peak right ventricular pressure did not produce significant hypertrophy even after 3 weeks. The right ventricular hypertrophy at the organ and cell levels in response to pressure-overload decreased with age. In vivo pressure-generating ability, which was determined by maximum isovolumic pressure during pulmonary artery occlusion, correlated with the degree of myocardial hypertrophy in each age group. During the ascending aortic constriction experiment the age-associated diminution in hypertrophic response was also observed in the left ventricle. Coronary dilator capacity, which was determined after brief ischemia in an isolated, blood-perfused, beating but nonworking heart model, was decreased in the presence of myocardial hypertrophy in young-adult rats (7 months) and in the absence of significant myocardial hypertrophy in old rats (18 months). The age-associated diminution in capacity for myocardial hypertrophy, pressure-generating ability and maladaptation in the coronary circulation may explain the higher incidence of heart failure or increased vulnerability of the myocardium to ischemic episodes during hemodynamic stress in aged patients.

Original languageEnglish
Pages (from-to)482-488
Number of pages7
JournalJAPANESE CIRCULATION JOURNAL
Volume56
Issue number5
DOIs
Publication statusPublished - 1992

Keywords

  • Age
  • Ascending aortic constriction
  • Cardiac hypertrophy
  • Coronary dilator reserve
  • Left ventricle
  • Pulmonary artery constriction
  • Rat
  • Right ventricle

ASJC Scopus subject areas

  • Physiology
  • Cardiology and Cardiovascular Medicine

Fingerprint

Dive into the research topics of 'Aging Effects on Myocardial Hypertrophic Response and Coronary Circulation in Pressure-Overload'. Together they form a unique fingerprint.

Cite this