Related Experiment Video
Updated: Jul 20, 2026

Echocardiographic and Histological Examination of Cardiac Morphology in the Mouse
Published on: October 26, 2017
Myocyte morphological characteristics differ between the phases of pulmonary hypertension-induced ventricular
Shunrou Minami1, Tatsuyuki Onodera, Fumiko Okazaki
1Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan.
Abstract:
Pulmonary hypertensive model rats were prepared by treating them with monochrotaline (MCT). Using these model rats, we examined myocyte remodeling in the right ventricle in response to increased right ventricular pressure. Male Sprague-Dawley rats were divided into 2 groups. Group M received MCT and group C received physiological saline. The 2 groups were examined at weeks 2, 5, and 7 after MCT or saline injection, respectively. At week 2, a significant difference in cell form was not observed in either group. At week 5, cell volume and myocyte cross-sectional area (CSA) of the right ventricle in group M were significantly greater than those in group C. At week 7, cell volume, CSA, and cell length of the right ventricle in group M were all significantly greater than those in group C. These results suggest that pulmonary hypertension causes hypertrophy, accompanying the enlargement of CSA in the right ventricle, and that cells lengthen in the phase of right ventricular failure. These results are similar to the changes observed in left ventricular myocytes due to overload pressure. Both right and left ventricular myocytes may share a common mechanism for myocyte remodeling as an adaptive and maladaptive response to increased ventricular pressure.
Related Concept Videos
Heart Failure II: Pathophysiology
Cardiomyopathy III: Hypertrophic Cardiomyopathy
Structure of Cardiac Muscles
Compared to skeletal muscles, cardiac muscle cells are small and mostly have a single nucleus. Additionally, they are usually...
Specialized Characteristics of Cardiac Muscles
Cardiac muscle cells are smaller than skeletal muscles, averaging 10–20 mm in diameter and 50–100 mm in length. However, they have large energy demands for continuous contraction and relaxation. This energy is almost exclusively derived from aerobic metabolism of energy reserves in...
Cardiomyopathy I: Introduction and Classification
Pathophysiology of Heart Failure

