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

Biochem J. 1987 Oct 15;247(2):407-15. doi: 10.1042/bj2470407.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Albumins / metabolism*
  • Animals
  • Cell Membrane Permeability / drug effects*
  • Cells, Cultured
  • Endoplasmic Reticulum / drug effects
  • Haptoglobins / metabolism
  • L-Lactate Dehydrogenase / metabolism
  • Liver / drug effects*
  • Liver / metabolism
  • Liver / ultrastructure
  • Male
  • Micelles
  • Microscopy, Electron
  • Rats
  • Rats, Inbred Strains
  • Saponins / pharmacokinetics*

Substances

  • Albumins
  • Haptoglobins
  • Micelles
  • Saponins
  • L-Lactate Dehydrogenase