Adaptation phenomena of adult cardiac myocytes in culture.

Adult ventricular muscle cells attach firmly on serum pretreated tissue culture dishes during the first 3 hours of incubation. During one week of serum-free culturing in M-199 medium their ultrastructure changes only little, as opposed to their behaviour in a coculture with hepatocytes. In culture, adjacent myocytes develop new intercellular contacts some of which exhibit the morphological characteristics of nexus. During one week in the monoculture, spontaneous beating is not observed, but in the coculture system it is found after three days in flat, structurally transforming cells.