Persistence of a Basal Lamina-Like Structure Following DOCA-Induced Myofibrillar Degeneration in Rats

It is known that the myocardial necrosis of potassium depletion heals by reconstitution and not by scarring, when animals are replenished with potassium. In the course of studies on DOCA-induced myofibrillar degeneration, we found that a membrane-like structure persisted in the area where the disintegrating myofiber was being removed by macrophages. This structure resembled the basal lamina, and enclosed a space in which macrophages with phagosomes containing disintegrating myofibral constituents were seen in association with undif-ferentiated cells. We postulate that this basal lamina-like structure along with the undifferentiated cells, play a role in the reconstitution of the myocardium during the stage of potassium repletion, and that the scaffolding by basal lamina may be effective in myocardial reconstitution.