Organ culture of rat myocardial slices: An alternative in vitro tool in organ-specific toxicology

Summary Precision-cut adult rat myocardial slices of highly consistent dimensions were produced and maintained for at least 24 h in an organ culture system. These relatively thin (350-400 pm) slices were generated from tissue cores (7 mm diameter) obtained from coring the sagittally slabbed myocardium. The tissue cores were then used to produce slices with a mechanical tissue slicer under specific temperature (25°C) and buffer (zero Ca²⁺, high K⁺) conditions. Myocardial slices are viable for at least 24 h in culture, as assessed by a biochemical battery including K⁺ and Ca²⁺ content, labeled leucine incorporation, ATP content, and the loss of the cytoplasmic enzyme LDH. In addition to these parameters, histological evaluation was also employed. These data indicate that the precision-cut myocardial slice system is a possible alternative in vitro tool and merits further study in the field of cardiotoxicity.