Cytosolic enzyme leakage from isolated smooth muscle preparations.

Several isolated smooth muscle preparations were shown to release cytosolic enzymes including adenosine deaminase, lactate dehydrogenase, and nucleoside phosphorylase under experimental conditions resembling those used in contractility or drug uptake studies. This enzyme leakage indicates significant general cell damage and suggests that experiments dealing with drug metabolism, binding, and uptake in isolated tissues must be interpreted with caution.