Gorshkova I A, Gorshkov B A, Stonik V A
Pacific Institute of Bioorganic Chemistry, Far East Branch of U.S.S.R. Academy of Sciences, Vladivostok.
Toxicon. 1989;27(8):927-36. doi: 10.1016/0041-0101(89)90104-9.
The effect of triterpene glycosides from holothurians on Na+-K+-ATPase of rat brain was investigated. The marine glycosides are irreversible inhibitors of the enzyme with an average I50 value of 10(-4) M. ATP had a low protective effect against inhibition. The inhibitory effect was increased by preincubation with MgCl2. There was alteration of the activation curve of Na+-K+-ATPase by NaCl and KCl in the presence of glycosides. Triterpene glycosides inhibited the K+-phosphatase activity, but to a smaller degree than the ATPase activity. Na+-K+-ATPase of pig kidney was less sensitive to the marine triterpene glycosides than the brain enzyme. The marine glycosides did not alter the specific binding of [3H]-ouabain to the Na+-K+-ATPase.
研究了海参三萜糖苷对大鼠脑Na+-K+-ATP酶的作用。这些海洋糖苷是该酶的不可逆抑制剂，平均半数抑制浓度（I50）值为10⁻⁴ M。ATP对抑制作用的保护作用较弱。预先用MgCl₂温育会增强抑制作用。在存在糖苷的情况下，NaCl和KCl改变了Na+-K+-ATP酶的激活曲线。三萜糖苷抑制K⁺-磷酸酶活性，但程度小于对ATP酶活性的抑制。猪肾的Na+-K+-ATP酶对海洋三萜糖苷的敏感性低于脑酶。海洋糖苷不改变[³H]-哇巴因与Na+-K+-ATP酶的特异性结合。
