A principal thrust of the research in Dr. Paolini's laboratory is to refine methods for assessing the contractile behavior of the cardiac muscle cell. Whole cell shortening and single sarcomere kinetics are measured in dissociated myocytes from adult rat heart, as are the perturbations produced by altered calcium ion levels and by pharmacological agents which cause changes in excitability and contractility.
Laboratory techniques utilized include video, fluorescence and electron microscopy.
Images are subjected to contrast enhancement and edge detection of sarcomeres or cell boundaries. Information extracted in real time from sequential cell images includes sarcomere length distributions, initial sarcomere shortening velocity, and relaxation time. Human heart failure is characterized by the inability of the heart to pump sufficient amount of blood to peripheral sites. Diminished pump function occurs as a consequence of the loss of viable myocardial tissue and a reduction of contractile strength of myocytes. An investigation of the contractility of individual left ventricular myocytes isolated from patients before and after LVAD insertion is under way to assess myocyte contractile changes during the course of recovery.