Effect of triterpene glycosides of marine invertebrates on permeability of biological and artificial membranes.

The influence of the triterpene glycosides holothurin and cucumariaside from Holothuria grissi and Cucumaria japonica, respectively, on the parameters of the active transport of calcium ions by vesicles of the sarcoplasmic reticulum and on the permeability of liposomes formed from the total fraction of egg phospholipids was investigated. It was found that at low concentrations these substances decrease the Ca-ATPase activity without noticeably increasing the permeability of the membranes, whereas at high concentrations they cause a sharp increase in the permeability of the membranes of Ca2+ ions.