ENDOTHELIUM OF MYOCARDIUM MICROVESSEL UNDER CONDITIONS OF HYPOTHERMIA, ISCHEMIA, REPERFUSION AND PHARMACO-COLD
CARDIOPLEGIA WITH CALCIUM ANTAGONIST
G. M. Kazanskaya, A. M. Volkov, Ò. Ì. Diakonitsa, G. P. Zhdanov
Research Institute of Circulation Pathology after Yu. N. Mcshalkin, Ministry of Public Health of
Russian Federation, Novosibirsk, Russia;
Microvessels of the right atrium endothelium were investigated with electron microscope for patients with congenital
heart disease receiving surgical treatment under deep perfusionless hypothermia and various methods of pharmaco-cold cardioplegia.
In group 1, pharmaco-cold cardioplegia was performed, with hyperosmolar normopotash solution cooled down to 2-4 °C. In group 2,
the same solution combined with isoptin, a potashion blocker, was applied. It has been shown that during global ischemia, stability
of ion gradients on plasmalemma of endothelial cells is impaired, irrespective of the composition of cardioplegia solution.
Alongside with this, ultrastractural reactions in group 1 proceed towards hyperosmia of endothelium accompanied by building up a
large group of cells following coagulation necrosis. In group 2, by contrast, an intracellular edema progresses. The cardioprotective
effect of isoptin, which is able to block Ca2+, manifests itself most vividly at reperfusion, when the blocking of cell
potash overload prevents the development of dystrophic and destructive changes in endothelium of coronary microvessels, which present
one of the most severe consequences in the process of blood flow recovery in ischemic tissues.
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