Wassler M, Westman J, Fries E
Department of Medical and Physiological Chemistry, University of Uppsala, Sweden.
Eur J Cell Biol. 1990 Apr;51(2):252-8.
The process by which a saponin derived from Gypsophila plants permeabilizes rat hepatocytes was studied. When monolayer cultures were incubated with 25 micrograms/ml saponin in phosphate buffered saline, the amount of cell-bound saponin increased for at least 90 min. Release of intracellular K+ started immediately, with a t1/2 of about 5 min. ATP and lactate dehydrogenase (LDH) began to appear in the medium only after lag periods of 10 to 20 min with t1/2s of 20 to 30 min. Removing the saponin from the medium after 15 min stopped any further release of ATP and LDH, showing that increased permeability to small ions alone does not lead to lysis by colloid osmotic pressure. However, the lysis that occurred upon 30 min continuous incubation with the saponin could be inhibited (delayed) by the addition of an osmotically active compound - a dextran. These results indicate that increasing binding of the saponin destabilizes the plasma membrane so that it will rupture from the colloid osmotic pressure.
研究了源自满天星属植物的皂苷使大鼠肝细胞通透化的过程。当单层培养物在磷酸盐缓冲盐水中与25微克/毫升皂苷一起孵育时，细胞结合的皂苷量至少增加90分钟。细胞内钾离子的释放立即开始，半衰期约为5分钟。ATP和乳酸脱氢酶（LDH）仅在10至20分钟的延迟期后才开始出现在培养基中，半衰期为20至30分钟。15分钟后从培养基中去除皂苷可阻止ATP和LDH的进一步释放，表明仅对小离子通透性增加不会导致胶体渗透压引起的细胞裂解。然而，与皂苷连续孵育30分钟时发生的细胞裂解可通过添加渗透活性化合物——葡聚糖来抑制（延迟）。这些结果表明，皂苷结合增加会使质膜不稳定，从而使其因胶体渗透压而破裂。
