Portman O W, Alexander M
J Lipid Res. 1970 Jan;11(1):23-30.
We studied the synthesis and hydrolysis of sphingomyelin by homogenates of aortic intima plus inner media from normal squirrel monkeys and from monkeys with nutritionally-induced atherosclerosis (6-10 mo on a semi-purified diet containing butter and cholesterol). The concentrations of sphingomyelin in the aortas and plasmas of the atherosclerotic monkeys were higher than those for the normal monkeys. Palmitoyl-1-(14)C coenzyme A was actively utilized for the synthesis of ceramide (N-palmitoyl sphingosine). The addition of sphingosylphosphorylcholine increased the utilization of palmitoyl CoA in sphingomyelin synthesis, and the addition of psychosine (sphingosyl galactoside) increased the incorporation of palmitate into cerebrosides. Rates of sphingomyelin and ceramide synthesis were significantly higher in the atherosclerotic than in the control aortas. Hydrolysis of labeled sphingomyelin to ceramide was also increased in homogenates of the atherosclerotic aortas. Labeled sphingomyelin was taken up from plasma by everted carotid arteries, and this process was also enhanced by atherosclerosis. Increased rates of synthesis and of uptake from plasma of sphingomyelin may account for the increased concentrations of sphingomyelin in the atherosclerotic arteries, even though the ability to degrade sphingomyelin is also enhanced in the atherosclerotic aorta.
我们研究了正常松鼠猴以及患有营养诱导性动脉粥样硬化的猴子（在含黄油和胆固醇的半纯化饮食中喂养6 - 10个月）的主动脉内膜加中膜匀浆对鞘磷脂的合成及水解情况。动脉粥样硬化猴子的主动脉和血浆中鞘磷脂浓度高于正常猴子。棕榈酰 - 1 -（14）C辅酶A被积极用于神经酰胺（N - 棕榈酰鞘氨醇）的合成。鞘氨醇磷酸胆碱的添加增加了棕榈酰辅酶A在鞘磷脂合成中的利用，而鞘氨醇半乳糖苷（psychosine）的添加增加了棕榈酸酯掺入脑苷脂的量。动脉粥样硬化主动脉中鞘磷脂和神经酰胺的合成速率显著高于对照主动脉。动脉粥样硬化主动脉匀浆中标记的鞘磷脂水解为神经酰胺的过程也有所增加。外翻的颈动脉从血浆中摄取标记的鞘磷脂，并且这一过程也因动脉粥样硬化而增强。鞘磷脂合成速率和从血浆摄取速率的增加可能解释了动脉粥样硬化动脉中鞘磷脂浓度的增加，尽管动脉粥样硬化主动脉中降解鞘磷脂的能力也增强了。
