Attachment and maintenance of adult rabbit cardiac myocytes in primary cell culture

The present observations demonstrate that quiescent calcium-tolerant adult rabbit cardiac myocytes can be isolated by collagenase-hyaluronidase perfusion and maintained in primary culture for at least 2 wk. Culturing large numbers of myocytes requires that the freshly isolated cells be attached to a suitable substratum such as laminin, type IV collagen, or fetal bovine serum. The cultured myocytes retain their rod-like morphology for approximately 7 days before gradually spreading into a flattened conformation by 14 days. During the 1st wk of culture, contaminating interstitial cells rapidly proliferate, making cultures unsuitable for long-term study. Pure myocyte populations can be established and maintained if freshly isolated cells are cultured in the presence of cytosine arabinoside (Ara-C, 10 microM). This antimetabolite does not appear to adversely affect high-energy phosphates, since ATP and creatine phosphate (CrP) content of the myocytes is maintained at levels normally found in biopsy samples of rabbit myocardium. These results illustrate that an energetically stable population of adult cardiac myocytes can be maintained in primary culture in sufficient numbers to make them useful for future investigations of myocyte function.