The effect of incubation on the weight of guinea pig cardiac muscle preparations

Abstract

Guinea pig atria and ventricular strips were found to lose weight during incubation in vitro. This weight loss is not measurably changed by incubation under anoxic conditions, at 20 °C, or in the presence of ouabain. The percent water of the preparations remained constant during weight loss. Various changes in sodium and potassium occurred in the two preparations and in the same preparation under different environmental conditions but did not correlate with the weight loss. The results demonstrated weight loss of equal parts water and solid from cardiac muscle during incubation in vitro with no serious alteration in cation concentrations. The loss is not altered by metabolic depression, suggesting a physical process.