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Differential permeabilization of membranes by saponin treatment of isolated rat hepatocytes. Release of secretory proteins.

ABSTRACT: Monolayer cultures of rat hepatocytes were treated with increasing concentrations of saponin (prepared from Gypsophila plants) for 30 min at 6 degrees C. Differential permeabilization of the intracellular membranes could be demonstrated: at 0.040 mg of saponin/ml the plasma membrane was permeabilized, as assessed by the release of 50% of the total cellular amount of lactate dehydrogenase, and at 0.20 mg/ml the endoplasmic reticulum was permeabilized, as measured by the release of 50% of pulse-35S-labelled albumin. The Golgi complex was permeabilized at an intermediate saponin concentration, as indicated by the release of homogeneously 35S-labelled albumin; about half the intracellular albumin is located in this organelle. At 1.0 up to 5.0 mg of saponin/ml 90-95% of the radioactively labelled albumin was released. Even at 5.0 mg/ml less than 10% of the membrane of the endoplasmic reticulum was solubilized, as judged by the degree of release of a membrane-bound enzyme specific for this organelle. These results demonstrate the usefulness of saponin as a tool for investigating the interior of different intracellular compartments.

SUBMITTER: Wassler M

PROVIDER: S-EPMC1148424 | biostudies-other | 1987 Oct

REPOSITORIES: biostudies-other

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Release of soluble resident as well as secretory proteins from HepG2 cells by partial permeabilization of rough-endoplasmic-reticulum membranes.

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Transient partial permeabilization with saponin enables cellular barcoding prior to surface marker staining.

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Evidence for G proteins in rat parotid plasma membranes and secretory granule membranes.

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