Establishment of Rat Model of Cardiopulmonary Bypass in Pulmonary Hypertension

Abstract

An experimental model of cardiopulmonary bypass in rats with pulmonary hypertension is necessary to understand underlying mechanisms and develop protective strategies. Male Sprague-Dawley rats were randomly divided into a sham group, cardiopulmonary bypass group, pulmonary hypertension group, and pulmonary hypertension with cardiopulmonary bypass group. Both groups with pulmonary hypertension received a subcutaneous injection of monocrotaline 60 mg x kg(-1) on day 0. Cardiopulmonary bypass was instituted in one of them 21 days later. The sham and pulmonary hypertension control groups underwent cannulation only. Cardiopulmonary bypass was conducted for 60 min at a flow rate of 100 mL x kg(-1) x min(-1). Hemodynamic investigations, blood gas analysis, interleukin-6, tumor necrosis factor-alpha, and survival studies were performed subsequently. Time-dependent increases of serum interleukin-6 and tumor necrosis factor-alpha were found after cardiopulmonary bypass in both groups. This model allows the study of multiple organ pathophysiological processes after cardiopulmonary bypass in rats with pulmonary hypertension, as well as the evaluation of possible protective strategies.