Effect of acetaldehyde on functioning of cardiac muscle at the ultrastructural level.

The effect of acetaldehyde, the hepatic metabolite of alcohol, on the functioning of cardiac muscle was investigated at the subcellular level. Concentrations of acetaldehyde that occur in plasma failed to alter either the microsomal Ca2+-accumulating and ATPase activity or the Ca2+-accumulating activity of the mitochondria. These same concentrations of acetaldehyde inhibited the Ca2+-dependent myofibrillar ATPase.