CHANGES IN ANDROGEN RECEPTOR EXPRESSION IN THE MYOCARDIUM OF RATS AFTER SUBMAXIMAL TRAINING AND NANDROLONE DECANOATE TREATMENT

Androgens and physical exercises influence the quantity and binding capacity of the androgen receptor (AR) in the muscles. The combined effect of endurance training and anabolic androgenic steroids (AAS) on the expression of AR in the myocardium have not been studied in depth. The single and the combined effect of the submaximal training and AAS on the AR in the myocardium and on the serum testosterone (Ts) levels of male rats have been examined. The main location of AR was in the cardiomyocyte nuclei and the nuclei of the cells from the vessel wall. We found that the application of AAS on untrained animals did not influence the number of AR positive cardiomyocyte nuclei but reduced the Ts levels (P < 0.05). Eight weeks of submaximal training increased the number (P < 0.01) of AR positive cardiomyocyte nuclei and created a tendency of decrease in serum Ts levels in comparison with the controls. Combining endurance training and AAS reduced the number of AR (P < 0.01) and the levels of Ts (P < 0.05) in comparison with the effect of the training alone. The results showed high reactivity of AR, in the myocardium to the endurance training and AAS. Data concerning the alteration of the nuclear AR expression in the cardiomyocytes during the single and combined influence of endurance training and AAS are presented for the first time.