The isolated perfused working mouse heart system

Study of cardioactive agents in vivo is complicated by neurohormonal influences and variations in loading conditions. The working mouse heart perfusion system allows for the ex vivo direct measurement of cardiac metabolism and function, and responses to drugs and hormones, under defined conditions. Myocardial pressure and volume measurements are obtained using a micro-tip catheter inserted into the left ventricular chamber. Direct and derived functional data include heart rate (HR), cardiac output (CO), end systolic pressure (ESP), end diastolic pressure (EDP), end systolic volume (ESV), end diastolic volume (EDV), stroke volume (SV), and ejection fraction (EF). Metabolic data include rates of glycolysis, glucose oxidation, and fatty acid oxidation. The mouse serves as an ideal model for evaluation of the pharmacology and toxicity of novel cardioactive therapeutics due to its rapid reproduction, low cost, and relevance to human physiology.