Effect of prolonged cold storage on the mechanical activity of rabbit atria

Even after 21 days of cold storage at 2 degrees C, rabbit atria still showed a detectable response only to isoproterenol while other cardiostimulants (norepinephrine, ouabain, anthopleurin-A and nicotine) failed to activate tissues stored up to 14 days. The specific fluorescence of catecholamines disappeared from the tissue after 5 days of cold storage. The maximum decrease in oxygen consumption and tissue catecholamine content was observed after 14 days and a concomitant decrease in tissue ATP content, Na+-K+, Ca2+ and Mg2+-ATPases was nearly maximal after 7 days of cold storage. The cold storage had no apparent effect on the ultrastructures of myocardial cells except a disappearance in glycogen granules.