Effects of Conditioning of Medium on Beating of Single Myocardial Cells In vitro

Abstract

Heart cells singly dissociated from mouse embryos were cul-tured at high (4 × 105 cells per plate) or low (0.5 × 105 cells per plate) density. After cultivation for one day, the percentages of beating cells were 51 % and 75 %, respectively, and the average beating rates were 39 beats/min (b/m) and 70 b/m, respectively. The average beating rate of single heart cells cultured at low density in the medium consisting of 3 parts of conditioned medium and 1 part of fresh medium was 72-85 b/m, while the value in the fresh medium was 40-57 b/m. Lung, kidney, skeletal muscle and L cells from mice, FL cells, chick embryonic cells and reptilian iguana heart cells were effective at high density in increasing both the percentage of beating cells and the average beating rate of mouse myocardial cells cultured at low density.