EFFECTS OF OKADAIC ACID ON THE ACTIVITIES OF 2 DISTINCT PHOSPHATIDATE PHOSPHOHYDROLASES IN RAT HEPATOCYTES
EFFECTS OF OKADAIC ACID ON THE ACTIVITIES OF 2 DISTINCT PHOSPHATIDATE PHOSPHOHYDROLASES IN RAT HEPATOCYTES
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DOI：
10.1016/0014-5793(92)80219-7
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发表时间：
1992-04-13
期刊：
影响因子：
3.5
通讯作者：
BRINDLEY, DN
中科院分区：
文献类型：
--
作者：
GOMEZMUNOZ, A;HATCH, GM;BRINDLEY, DN
用冈田酸孵育肝细胞将N-乙基马来酰亚胺敏感的磷脂酸磷酸水解酶从膜部分转移到细胞质中，并部分阻止油酸诱导的磷酸水解酶从细胞质到膜的移动。然而，较高浓度的油酸仍然引起磷酸水解酶的易位和激活。该酶受 Mg2+ 刺激，可能参与甘油脂的合成。冈田酸还降低肝细胞内二酰甘油的浓度。冈田酸对 N-乙基马来酰亚胺不敏感的磷脂酸磷酸水解酶的活性没有明显影响，该酶仍然牢固地附着在膜上。该活性不受 Mg2+ 刺激，可能参与磷脂酶 D 途径的信号转导。
Incubation of hepatocytes with okadaic acid displaced the N-ethylmaleimide-sensitive phosphatidate phosphohydrolase from the membrane fraction into the cytosol and partially prevented the oleate-induced movement of phosphohydrolase from cytosol to membranes. However, higher concentrations of oleate still caused translocation and activation of the phosphohydrolase. This enzyme is stimulated by Mg2+, and is probably involved in glycerolipid synthesis. Okadaic acid also decreased the concentration of diacylglycerol within the hepatocytes. Okadaic acid had no observable effect on the activity of an N-ethylmaleimide-insensitive phosphatidate phosphohydrolase which remained firmly attached to membranes. This activity is not stimulated by Mg2+ and is probably involved in signal transduction by the phospholipase D pathway.