In many epileptic patients, anticonvulsant drugs either fail adequately to control seizures or they cause serious side effects. An important adjunct to pharmacologic therapy is the ketogenic diet, which often improves seizure control, even in patients who respond poorly to medications. The mechanisms that explain the therapeutic effect are incompletely understood. Evidence points to an effect on brain handling of amino acids, especially glutamic acid, the major excitatory neurotransmitter of the central nervous system. The diet may limit the availability of oxaloacetate to the aspartate aminotransferase reaction, an important route of brain glutamate handling. As a result, more glutamate becomes accessible to the glutamate decarboxylase reaction to yield gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter and an important antiseizure agent. In addition, the ketogenic diet appears to favor the synthesis of glutamine, an essential precursor to GABA. This occurs both because ketone body carbon is metabolized to glutamine and because in ketosis there is increased consumption of acetate, which astrocytes in the brain quickly convert to glutamine. The ketogenic diet also may facilitate mechanisms by which the brain exports to blood compounds such as glutamine and alanine, in the process favoring the removal of glutamate carbon and nitrogen.

中文翻译：

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生酮饮食和氨基酸的大脑代谢：与抗惊厥作用的关系。

在许多癫痫患者中，抗惊厥药要么不能充分控制癫痫发作，要么会引起严重的副作用。生酮饮食是药物治疗的重要辅助手段，即使在对药物反应不佳的患者中，通常也可以改善癫痫发作的控制。解释治疗效果的机制尚不完全清楚。有证据表明，氨基酸对大脑的处理有影响，尤其是谷氨酸，这是中枢神经系统的主要兴奋性神经递质。饮食可能将草酰乙酸的可用性限制在天冬氨酸转氨酶反应中，这是脑处理谷氨酸的重要途径。结果，更多的谷氨酸可用于谷氨酸脱羧酶反应以产生γ-氨基丁酸（GABA），主要的抑制性神经递质和重要的抗癫痫药。此外，生酮饮食似乎有利于谷氨酰胺的合成，谷氨酰胺是GABA的重要前体。发生这种情况的原因既有酮体碳代谢为谷氨酰胺，又是因为在酮症中，醋酸盐的消耗量增加了，大脑中的星形胶质细胞迅速转化为谷氨酰胺。生酮饮食还可以促进大脑向血液中的化合物（例如谷氨酰胺和丙氨酸）输出的机制，从而有利于去除谷氨酸碳和氮。大脑中的星形胶质细胞会迅速转化为谷氨酰胺。生酮饮食还可以促进大脑向血液化合物（例如谷氨酰胺和丙氨酸）输出的机制，在此过程中有利于去除谷氨酸碳和氮。大脑中的星形胶质细胞会迅速转化为谷氨酰胺。生酮饮食还可以促进大脑向血液中的化合物（例如谷氨酰胺和丙氨酸）输出的机制，从而有利于去除谷氨酸碳和氮。