Effects of Chronic Mild Stress on Cardiac Autonomic Activity, Cardiac Structure and Renin–Angiotensin–Aldosterone System in Male Rats

Figures

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  Figure 1. Overview of the experiment time course for CMS and ECG recording.

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  Figure 2. Body weight (A) and average daily food intake (B) of control and CMS. * p < 0.05; ** p < 0.01; *** p < 0.001 vs. control at the same time point, ### p < 0.001 vs. baseline (week 0) within group, two-way repeated measures ANOVA followed by Dunnett’s; n = 7 for each group.

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  Figure 3. Sucrose intake of control and CMS. Data are presented as mean ± S.E.M. ** p < 0.01, *** p < 0.001 vs. control at the same time point, ## p < 0.01 vs. baseline (week −1) within group, two-way repeated measures ANOVA followed by Dunnett’s, n = 7 for each group.

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  Figure 4. Normalized data of VLF (A), LF (B), HF (C) and LF/HF ratio (D) of control and CMS. Data are presented as mean + S.E.M., * p < 0.05 vs. control, ** p < 0.01 vs. control at the same time point, Student’s unpaired t-test; n = 7 for each group.

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  Figure 5. Histological sections of left ventricle in control (A) and CMS (B), and box plot of quantitative analysis of cardiomyocyte cross-sectional area (C). H&E, 400×; scale bar = 20 µm; n = 7 for each group.

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  Figure 6. Box plots of RAAS including Ang II concentration (A), angiotensin-converting enzymes (ACE and ACE2) (B) and angiotensin receptors (AT1R and AT2R) (C) in control and CMS groups. * p < 0.05 vs. control using Student’s unpaired t-test; n = 4–7 for each group.

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  Figure 7. Correlative analysis between stress-, HRV-, cardiac- and RAAS-related indices. The correlative values are shown with the gradient color of green to red ranging from +1 to −1; numbers in bold and italic represent p < 0.05 and 0.05 < p < 0.10, as determined by Pearson correlation; n = 13–14. Abbreviations: BW, body weight; CA, cardiomyocyte area; pBNP, plasma BNP; rAdrenal, relative adrenal gland weight; rHeart, relative heart weight; SIT, normalized sucrose intake test.