Correlation between adolescent chronic emotional stress and incidence of adult cardiovascular disease in female rats

Objective(s): Association of adolescent emotional stress (ES) with the incidence of cardiovascular disease (CVD) at older age was investigated. Materials and Methods: 21 female rats were divided into three groups of 7 each; ES, foot-shock, and control. Chronic ES was induced by exposing the rats to witness foot-shock of their neighboring counterparts in the stress-box system in 5 successive days. 6 weeks after the last stress exposure, M-Mode echocardiographic assessment, qRT-PCR, and western blotting were performed in adult rats to determine the persistent effect of adolescent ES on cardiac performance and gene/protein expression levels of cardiac natriuretic peptide receptor 3 (NPR3) as a biomarker of CVD. Results: Interventricular septum thicknesses in diastole (IVSd) increased from 0.152±0.007 cm to 0.197±0.016 cm (P<0.05), left ventricular posterior wall thickness in diastole (LVPWd) significantly enlarged from 0.169±0.006 cm to 0.288±0.033 cm (P<0.01), left ventricular posterior wall thickness in systole (LVPWs) enlarged from 0.223±0.012 cm to 0.318±0.038 cm (P<0.05), left ventricular mass increased from 1.000±0.024 g to 1.283±0.084 g (P<0.01), and mean heart rate elevated from 229.42±6.57 bpm to 280.29±10.45 bpm (P<0.01). Moreover, ES significantly upregulated the expression levels of cardiac NPR3 gene (P<0.01) and protein (P<0.01). Conclusion: The incidence of adult CVD seemed to be increased under the influence of adolescent ES. Consequently, we suggest that mental healthcare during adolescence would be a critical factor for adult CVD prevention.