Enzyme release.
Enzyme release was studied in various tissues in intact animals or by means of tissue slices, organ perfusion or isolated and cultured cells. The factors that determine the extent and the time course of the leakage were studied extensively with several liver enzymes. It was found that the molecular properties of the enzymes, their topology within the organ, their intracellular localisation, their inducibility on the one hand, the nutritional and energetic state of the organ, and the respective protein turnover on the other, and finally, the type of the organ lesion all contribute to the different release patterns, which are known from experimental studies, and which are utilized for the diagnosis of diseases. While these preconditions of enzyme release are fairly well understood, the nature of the membrane alterations and the mechanism of detachment and transport of the enzyme proteins are less clear. Different models have been proposed, which may not exclude each other. Alterations of the cytoskeleton and the lipid composition of the plasma membranes are closely linked to ion imbalance, which is, in turn, dependent on the energy state of the individual cellular compartments.
Schmidt
E
E
Abt. Gastroenterologie und Hepatologie, Medizinische Hochschule Hannover, FRG.
Schmidt
F W
FW
D000818:Animals; D004798:Enzymes / Q000378:metabolism*; D006801:Humans
D004798:Enzymes