Perforated hepatocytes as a system for studying intracellular proteolysis.

ABSTRACT

Isolated rat hepatocytes were treated either by electroshock or enterotoxin in order to perforate the plasma membrane. Under appropriate conditions perforated cells could be incubated for a couple of hours without further disruption. The rate of proteolysis was higher in the perforated cells than in homogenized cells. ATP, a thiol reagent and Ca2+/Mg2+ stimulated proteolysis. By using inhibitors, it was shown that the proteolysis was partly lysosomal, and that all four classes of endoproteinases were involved.