Cardiac remodeling in rats with renal failure shows interventricular differences

Area of Science:

• Cardiovascular Physiology
• Nephrology
• Cardiac Remodeling

Background:

• Chronic renal failure (CRF) elevates cardiovascular disease risk.
• Cardiac alterations in CRF are known, but interventricular differences in remodeling remain unexplored.
• Investigating these differences is crucial for understanding CRF's cardiac impact.

Purpose of the Study:

• To investigate interventricular differences in cardiac structural and contractile remodeling in a rat model of chronic renal failure (CRF).
• To characterize changes in left ventricle (LV) and right ventricle (RV) function and cellular structure.

Main Methods:

• CRF was induced via two-stage 5/6 nephrectomy (NX) in male Wistar rats.
• Cardiac hypertrophy was assessed using ventricle/body weight ratios and myocyte morphometrics.
• Contractile force and membrane potential were measured in isolated papillary muscles.

Main Results:

• NX rats exhibited LV hypertrophy but not RV hypertrophy.
• LV papillary muscles showed reduced contraction force, while RV papillary muscles demonstrated enhanced force.
• Action potential durations were shortened in both ventricles; lithium partially restored LV force.

Conclusions:

• Cardiac remodeling in CRF presents significant interventricular disparities.
• CRF induces LV hypertrophy with contractile dysfunction, contrasting with RV hypertrophy and enhanced contractility.
• The Na+/Ca2+ exchanger may play a role in LV contractile dysfunction recovery in CRF.