Objectives: Stress increases the risk of cardiac diseases, including heart attack and sudden death. In this study, we aimed to investigate the histological changes of the myocardium of stress-exposed rats.
Methods: Twelve-male rats were randomly divided into control (n=6) and stress groups (n=6). Chronic mild stress procedure was applied to the rats of stress group during four weeks. At the end of the experiment, rats were sacrificed under anesthesia and blood samples were taken for assessments of serum cortisol level. Subsequently, the hearts were removed and the volume of each heart was measured by using water immersion method. After routine histologic procedure, sections were stained with Haematoxylin-Eosin and evaluated under the light microscope.
Results: The volumes of hearts of the stress group were found significantly increased when compared to the control group (p<0.05; Mann-Whitney U Test). Pericellular oedema, cytoplasmic swelling and necrotic degenerations of cardiac muscle cells were observed in the sections of the stress-exposed rats. Also, myocardial blood vessels were enlarged. Additionally, it was noticeable that there were prominent oedema, mononuclear cell infiltration and many adipocytes in perivascular areas.
Conclusions: According to our findings, it was concluded that chronic stress could cause cardiac damage by adversely affecting normal histological structure of the heart muscle.