Relation between spontaneous activity and cholinesterase activity of dissociated embryonic and young rat-heart and embryonic chick-heart cells studied in tissue culture

Summary The number of spontaneously beating single cells obtained both from rat and chick hearts disaggregated by trypsin, is age-dependent: it is higher in younger than in older hearts. Cholinesterase activity and glycogen content are high in the spontaneously active cells. Being dependent on animal age, many Cholinesterase and PAS-positive cells are present in cultures prepared from early hearts. Succinicacid dehydrogenase-activity is equally feeble in spontaneously active and inactive heart cells. Only in older, already differentiated cells, devoid of spontaneous activity, is it intense.