Left ventricular hypertrophy in rats with biliary cirrhosis

Area of Science:

• Cardiovascular Physiology
• Hepatology
• Endocrinology

Background:

• Portal hypertension is linked to neuroendocrine activation and hyperdynamic circulation.
• The impact of portal hypertension on cardiac structure and function requires further investigation.

Purpose of the Study:

• To investigate the effects of intrahepatic portal hypertension on heart structure and function in a rat model.
• To explore the role of nitric oxide (NO) synthesis in cardiac changes associated with portal hypertension.

Main Methods:

• Induction of intrahepatic portal hypertension via chronic bile duct ligation (CBDL) in Sprague-Dawley rats.
• Assessment of hemodynamic parameters, cardiac index, heart weight, and myocardial NO synthesis.
• Histomorphometric analysis of cardiomyocytes and evaluation of gene expression (ANF, CK-B, eNOS).

Main Results:

• CBDL rats exhibited increased plasma angiotensin-II and endothelin-1, reduced peripheral and pulmonary resistance, and elevated cardiac index and heart weight.
• Significant left ventricular (LV) hypertrophy with increased cardiomyocyte width and length was observed, without changes in LV cavity or right ventricle (RV).
• Increased myocardial NO synthesis, elevated ANF and CK-B gene expression, and reduced coronary resistance (NO-dependent) were noted.

Conclusions:

• Portal hypertension associated with biliary cirrhosis induces significant LV hypertrophy and increased myocardial NO synthesis.
• These cardiac changes occur without detectable fibrosis or functional impairment.
• Findings may be relevant for understanding cardiac implications in patients with cirrhosis.