[Ultrastructural changes in the myocardium in immune damage to the heart]

Ultrastructural changes of cardiomyocytes were studied 1 hour after a local treatment of a dog heart with an anticardiac cytotoxic serum. It is shown that the immune treatment results in the destruction of glycocalix and formation of defects in the cardiomyocytes sarcolemma revealed by means of an electron-microscopic tracer-colloid lanthanum. Preliminary block of calcium channels by verapamil decreases the degree of ischemic myocardium damage. However the use of verapamil does not prevent the defect formation in sarcolemma and, consequently, the disturbance of intracellular ion homeostasis, the morphological proof of this being the destructive changes in the myocardium characteristic of the "calcium type" damage.