Related Experiment Video
Updated: Jun 23, 2026
Establishment and Validation of a Rat Model of Pulmonary Arterial Hypertension Associated with Pulmonary Fibrosis
Published on: May 23, 2025
Reduced surface tension normalizes static lung mechanics in a rodent chronic heart failure model
Dani-Louise Dixon1, Carmine G De Pasquale, Hilde R De Smet
1Intensive and Critical Care Unit, Flinders Medical Centre, Bedford Park, Adelaide, South Australia 5042, Australia. dani.dixon@flinders.edu.au
Rationale:
Chronic elevation of pulmonary microvascular pressure in chronic heart failure results in compensatory changes in the lung that reduce alveolar fluid filtration and protect against pulmonary microvascular rupture.
Objectives:
To determine whether these compensatory responses may have maladaptive effects on lung function.
Methods:
Six weeks after myocardial infarction (chronic heart failure model) rat lung composition, both gross and histologic; air and saline mechanics; surfactant production; and immunological mediators were examined.
Measurements And Main Results:
An increase in dry lung weight, due to increased insoluble protein, lipid and cellular infiltrate, without pulmonary edema was found. Despite this, both forced impedance and air pressure-volume mechanics were normal. However, there was increased tissue stiffness in the absence of surface tension (saline pressure-volume curve) with a concurrent increase in both surfactant content and alveolar type II cell numbers, suggesting a novel homeostatic phenomenon.
Conclusions:
These studies suggest a compensatory reduction in pulmonary surface tension that attenuates the effect of lung parenchymal remodeling on lung mechanics, hence work of breathing.
