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Updated: Jul 12, 2026
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Published on: February 20, 2017
Left ventricular response to beta-adrenergic stimulation in aging rats
S Masson1, B Arosio, F Fiordaliso
1Department of Cardiovascular Research, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy. masson@irfmn.mnegri.it
Summary
Aging Wistar rats show preserved left ventricular adaptation to beta-adrenergic stimulation, despite increased fibrosis. This suggests aged hearts can still respond to stress, important for understanding heart failure in older populations.
Area of Science:
- Cardiology
- Gerontology
- Molecular Biology
Background:
- Heart failure incidence rises with age, often linked to sympathetic nervous system overactivation.
- Aging impacts cardiac function and response to stress, crucial for understanding age-related cardiovascular diseases.
Purpose of the Study:
- To investigate the influence of aging on short-term left ventricular (LV) adaptation to beta-adrenergic stimulation in Wistar rats.
- To compare the cardiac response to isoproterenol in young versus aged rats.
Main Methods:
- Assessed LV adaptation to isoproterenol (ISO) in 3-month-old and 18-month-old Wistar rats.
- Measured LV weight, myocyte dimensions, and gene expression (mRNA) of cardiac remodeling markers.
Main Results:
- Aged rats exhibited increased interstitial fibrosis compared to younger rats.
- Both age groups showed similar increases in LV weight and myocyte dimensions post-ISO treatment.
- Upregulation of genes related to extracellular matrix proteins was observed in aged rats following beta-adrenergic stimulation.
Conclusions:
- Despite age-related fibrosis, aged rat hearts maintain adaptive capacity to beta-adrenergic stimulation.
- The study highlights preserved cardiac gene regulation in response to stress in aging hearts.
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