Research in Experimental Medicine

, Volume 186, Issue 4, pp 295–306 | Cite as

The ultrastructure of the myocyte in different regions of experimental infarcts in the cat heart

  • T. H. Larsen
  • T. Sætersdal
  • K. Grong
Original Papers

Summary

The ultrastructure of myocytes was studied in the left ventricular myocardium of the cat heart after 3h of LAD ligation. The ischemic, borderline, and normally perfused myocardium was defined by in vivo injection of fluorescein and by regional myocardial blood flow measurements with 15.5 µm radio-labeled microspheres. A semiquantitation of the number of irreversible injured cells in per cent of total counted in the three different zones showed that 53%–63% were irreversibly injured in the ischemic zone, 7%–26% in the borderline area, while none were irreversibly injured in the normally perfused myocardium. The interior excitation-contraction couplings in the normally perfused myocardium comprise interior dyads, triads, reversed triads, and encircling couplings. While the couplings in general were structurally resistant to ischemia, injured interior couplings were apparent in severely damaged cells of the hypoperfused tissue. Such injuries comprise a widening of the junctional gap and a disintegration of the junctional processes.

Key words

Coronary blood flow Myocardial ischemia Border zone Irreversible cellular injury Fragmentation of sarcolemma Interior couplings 

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Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • T. H. Larsen
    • 1
  • T. Sætersdal
    • 1
  • K. Grong
    • 2
  1. 1.Institute of AnatomyUniversity of BergenBergenNorway
  2. 2.Surgical Research LaboratoryUniversity of BergenBergenNorway

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