Levade T, Salvayre R, Douste-Blazy L
J Neurochem. 1983 Jun;40(6):1762-4. doi: 10.1111/j.1471-4159.1983.tb08153.x.
Hydrolysis of sphingomyelin and 2-N-(hexadecanoyl)-amino-4-nitrophenyl-phosphorylcholine (HDA-PC), a synthetic analogue of sphingomyelin, by acid and Mg-dependent neutral sphingomyelinases was tested with a homogenate of normal human brain cortex. Results demonstrated quite different substrate specificities for these enzymes. Acid sphingomyelinase, which is neither activated by MgCl2 nor inhibited by EDTA, hydrolyzed both substrates (the hydrolysis ratio of HDA-PC to sphingomyelin is approximately 2). In contrast, Mg-dependent neutral sphingomyelinase, which is inhibited by EDTA and reactivated by MgCl2, hydrolyzed only sphingomyelin (the hydrolysis ratio of HDA-PC to sphingomyelin is approximately 0-0.05). This synthetic substrate seems to be useful for selective determination of acid sphingomyelinase and for avoiding interference of Mg-dependent neutral sphingomyelinase.
利用正常人脑皮质匀浆检测了酸性和镁依赖性中性鞘磷脂酶对鞘磷脂和2-N-(十六烷酰基)-氨基-4-硝基苯基-磷酰胆碱（HDA-PC，鞘磷脂的一种合成类似物）的水解作用。结果表明这些酶具有截然不同的底物特异性。酸性鞘磷脂酶既不受MgCl₂激活，也不受EDTA抑制，可水解两种底物（HDA-PC与鞘磷脂的水解率约为2）。相比之下，镁依赖性中性鞘磷脂酶受EDTA抑制并可被MgCl₂重新激活，仅水解鞘磷脂（HDA-PC与鞘磷脂的水解率约为0-0.05）。这种合成底物似乎可用于选择性测定酸性鞘磷脂酶，并避免镁依赖性中性鞘磷脂酶的干扰。
