Assay of Activities in the Cellular Compartment

The two-step procedure just discussed serves to disrupt the samples in group I for the purpose of separating the cells from the extracellular fluids. This 

Another method entails the addition of chemicals (drugs) that by virtue of their specificity will produce lysis of one or two cell layers, leaving a single cell type unaffected (Fig. 5.5B). 

Even after a homogeneous population of cells has been obtained from an organ or tissue, it is important to remember that when comparing the results of enzyme activity studies obtained on cells from one animal with those from another, differences in the ages of the animals, their genetic backgrounds, or even their nutritional status can alter the enzymatic activities recovered in their cells. 

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