Structural and functional aspects of adaptation of the heart to physical activity
The work was performed at the Department of normal anatomy of the Ternopil state medical Academy
In experiment investigated the structural and functional features of the
reorganization of the departments of the myocardium of experimental animals with a systematic physical activities. Installed, topologie accompanied by hypertrophy and dilatation, and these processes predominate in the left ventricle. Blood pressure under the effect of physical training decreases, as well as ongoing developments in the regulation of cardiac muscle in the direction of the predominance of the influence of the vagus nerve.
Keywords: heart, adaptation, physical exercise.
In this experiment it isinvestiigated structural-functional peculiarities of the reformation of sections of myocardial — experimental animals during dynamic physical loadings. It is ascertained that those are the last accompanied by hypertrophy and dylatation, and the se processes predominate in the left ventricular. Arterial pressure descreases under the influence of physicaltraining and some displacements also take place in regulation of the heart muscle to the prevalence of vagus influence.
Key words: heart, physical loadings, adaptation.
Adequate assessment of the structural and functional features of adaptive changes of the heart during exercise is one of the oldest and by far not yet studied the problems of sportevenementen and morphology [1,3,4].
Despite the numerous studies devoted to this problem, the scientific literature there are conflicting views on hypertrophy of heart muscle in athletes and on the functional and morphological changes hypertrophied hearts [3,8].
Given the above, the aim of this work was the study of the structural-functionaldisability realignment of the divisions of the myocardium of experimental animals during dynamic exercise.
Material and methods research
The experiments were performed on 70 Mature male rats of Wistar line weight 182,0-190,0 g within 2 months swam in water at a temperature of about 30 ° C. a one-Time animals stay in the water uvelichivaetsya.poetomu from 3 to 60 minutes. 17 animals of the same sex, age and weight who were in standard conditions of vivarium, formed the control group.
When studying the functional state of the cardiovascular system measured arterial pressure using plethysmometer apparatus , conducted the recording of electrocardiograms on electrocardiograph EC 2T-02 3-otwedeniah at a speed of movement of the tape 100 mm / s. thus for the calculation and analysis of various indicators of cardiac rhythm were recorded at least 100 of RR-intervals in the second abstraction .
By the method of variation statistics were determined the mean value of RR intervals (M), mean square deviation ((), variational scale ((X), mode (Mo), amplitudami (AMO), the coefficients of asymmetry (As) and kurtosis (Ex) , which are widely used to assess the heart rate. According to the formulas vicheslyali the tension index (ti) of the regulatory systems, the index of vegetative equilibrium (PSI), the adequacy of the processes of regulation (PAPR), vegetative indicator rhythm .
Euthanasia of animals was performed using rapid decapitation.Heart cut on K. I. Esipova (1981), separately weighed departments of the myocardium was performed planimetry of the endocardial surfaces of the heart , histometric measurement of isolated cardiomyocytes . This takes into account such morphometric parameters: the pure weight of the heart muscle (DIS) — the mass of the heart muscle without valves and major blood vessels, the absolute weight of the left (MLS)and right (MPS) ventricles — the mass of the ventricle is proportional to its mass part of the interventricular septum, ventricular index (W) — attitude MPS to MLS, the Fulton index (if) — the ratio of the mass of the left ventricle with the interventricular septum to the mass of the right, cardiac index (SI) is the ratio of the DIS to the body weight, the weight of the left (MLP) and right (WFP) fibrillation, indexproperty (SP) — the ratio of the MLP to WFP, the mass content of the left and right ventricles and Atria (% LV,% PH,% PL,% PP), the area of the endocardial surface of the left and right ventricles (PALS, PEPPS), planimetric index (PI) is the ratio PALS to PEPS, the diameters of cells and nuclei of the ventricles and Atria (DCLS, DEALS, DCPS, GAPS, DCLP, DELP,SPSC, DAP), nuclear-cytoplasmic index (ATSILS, AZIPS, ACELP, ACIPP). The relationship between functional and structural parameters were determined using correlation analysis  with the definition of the correlation coefficients ®. The power relationships between them were evaluated by four degrees : strong (r = 0.7 to 0.9), significant (r = 0.5 to 0.7), moderate (r = 0.3-0, 5), small (r(0,3). Experimental animals were divided into 3 groups. group 1 consisted of 19 rats that have not found a predominance of one of the divisions of the autonomic nervous system 2nd — 39 animals in which there was increased parasympathetic influences on the heart; 3-I — 12 rats with a clear predominance of the sympathetic division of the autonomic nervous system in regularizations heart muscle. Quantitative indicators were processed statistically, the differences between the comparative parameters were determined by the Student t-test.
Results and discussed
The obtained data of cardiometry presented in table. 1. The data analysis of the table showed that all 3 groups DIS was increased. In this case hypertrophy of the heart was held for contrast mass of all parts of the heart. Hypertrophic process in the departments of infarction was expressed differently, as evidenced by changes in MI and d’if. A statistically significant increasing if and decreasing AI pointed to the fact that during dynamic exercise left ventricular hypertrophy predominated.
Systematic physical activity was also accompanied by rasshireniyami heart, as evidenced by the dynamics PSLS, PSPSH, PSLP, DON. The growth of this PI pointed to the fact that in these experimental conditions was dominated by dilatation of the left ventricle.
It should be noted that hypertrophy of the parts of the heart took place due to thickening of cardiomyocytes. The latter is confirmed by the growth of their diameters and increase in diameters of cores.Nuclear-cytoplasmic ratio is not violated, as indicated on the structural stability of homeostasis at the cellular level .
The degree of hypertrophy of the parts of the heart was a little in the 1st group of observations (normotonic). So, in these animals, the mass of the left ventricle grew 13.9%, right — by 7.0%, left atrium 12.9%, pravoobladaniya — 9.1%. Similar increase of the spatial characteristics of the parts of the heart (PSLS, PSPSH, PSLP DOPN). This suggests that in the hearts of this group there is no disturbance between manometrically and spatial parameters of their parts.
Dynamics of morphometric parameters of the heart parts of white rats
when Fizicheskaya (M ± m)
Indicator Group observations
control first second third
1 2 3 4 May
DIS, mg 776,0 ± 13,2 868,60 ± 12,9 ** 908,10 ± 12,60 ** 916,20 ± 12,30 **
MLS, mg 482,7 ± 8, 7 550,10 ± 8,4 ** 578,4 ± 9,3 582,20 ± 8,1
MPS, mg 212,3 ± 4,5 227,20 ± 4,2 * 235, 6 ± 5,1 237,8 ± 4,8