DAMAGING INFLUENCE OF LOW TEMPERATURES ON CARDIOMYOCYTES MYOFIBRILS

Abstract

The work shows the experimental data about the influence of low temperatures on the structure of myofibrils of rabbits cardiomyocytes. The animals were cooled during 5, 15 and 30 days at the temperature of -30ºС daily for three hours. Electronic-microscopic and biophysical study of the structure and the functional activity of myocardium was done. The damages of morphofunctional state of cardiomyocytes myofibrillar apparatus were found out; the square of their damage was defined with the use of «Bio Vision» software depending on the density of myofibrils spots; the calculation of the percentage to the studied mass of myofibrils was done. After 5-day cooling, the square of the damaged spots of cardiomyocytes myofibrils was 1842.19 Sqr micr or 1.73% from the general square of myofibrils. The further cooling led to a more severe myocardial damage. At the 15^th day of cooling the damaged spots were 1961.631 Sqr micr or 11.59% from the general square of myofibrils and by the 30^th day the zone of the damage enlarged till 2042.56 Sqr micr or 15% from the general square of myofibrils. The obtained results suggest that a long cooling of the body is a severe damaging factor which affects cardio-vascular system. It influences metabolic processes in cardiomyocytes particularly negatively and causes the damage of myofibrillar apparatus of cells. The body being under cooling for a long time may get into unfavorable conditions for the normal heart work, which is revealed through the decrease of the functional myocardial working efficiency.