Beaugé F, Mangeney M, Nordmann J, Nordmann R
Adv Exp Med Biol. 1980;132:393-402. doi: 10.1007/978-1-4757-1419-7_39.
The effects of the various naturally occurring amino acids on ethanol oxidation in hepatocytes from 18-hrs starved and fed rats were studied. In order to minimize the non-ADH pathways and to avoid interference with the liver amino acid uptake the ethanol concentration used was 4 mM, the amino acids being added at the same concentration. In hepatocytes from starved rats, asparagine, serine, ornithine, hydroxyproline, histidine, cysteine, alanine, glycine, glutamate, glutamine, aspartate and arginine significantly increase ethanol consumption. The stimulatory effect of glutamine being much less pronounced than the asparagine one and proline being devoid of action, the influence of ammonium chloride addition on ethanol consumption in the presence of these amino acids was studied. Ammonium chloride determines an enhancement of ethanol oxidation, the results showing, contrarily to previous data, no apparent correlation between intracellular glutamate concentration and ethanol oxidation rate but rather a relation with aspartate concentration. In hepatocytes from fed rats alanine, asparagine, cysteine, glycine, hydroxyproline, ornithine and serine still increase ethanol oxidation, although to a lesser extent than in cells from starved rats. It appears that only amino acids which are precursors of either pyruvate or aspartate or glutamate are able to activate the ethanol oxidation. Pyruvate, aspartate and glutamate supply malate-aspartate shuttle components especially in cells from starved rats, pyruvate allowing direct cytosolic reoxidation of NADH in cells from fed rats as well as from starved rats. The relative strengths of the stimulatory effect could be roughly dependent on energy demand for glucose synthesis in starved rats and for urea synthesis in fed rats.
研究了各种天然存在的氨基酸对18小时饥饿和喂食大鼠肝细胞中乙醇氧化的影响。为了尽量减少非乙醇脱氢酶（ADH）途径并避免干扰肝脏对氨基酸的摄取，所用乙醇浓度为4 mM，氨基酸以相同浓度添加。在饥饿大鼠的肝细胞中，天冬酰胺、丝氨酸、鸟氨酸、羟脯氨酸、组氨酸、半胱氨酸、丙氨酸、甘氨酸、谷氨酸、谷氨酰胺、天冬氨酸和精氨酸显著增加乙醇消耗。谷氨酰胺的刺激作用远不如天冬酰胺明显，脯氨酸无作用，因此研究了在这些氨基酸存在下添加氯化铵对乙醇消耗的影响。氯化铵可增强乙醇氧化，结果表明，与先前数据相反，细胞内谷氨酸浓度与乙醇氧化速率之间无明显相关性，而与天冬氨酸浓度有关。在喂食大鼠的肝细胞中，丙氨酸、天冬酰胺、半胱氨酸、甘氨酸、羟脯氨酸、鸟氨酸和丝氨酸仍可增加乙醇氧化，尽管程度低于饥饿大鼠细胞。似乎只有丙酮酸、天冬氨酸或谷氨酸的前体氨基酸能够激活乙醇氧化。丙酮酸、天冬氨酸和谷氨酸提供苹果酸-天冬氨酸穿梭成分，尤其是在饥饿大鼠的细胞中，丙酮酸可使喂食大鼠和饥饿大鼠细胞中的NADH直接在胞质中再氧化。刺激作用的相对强度可能大致取决于饥饿大鼠中葡萄糖合成和喂食大鼠中尿素合成的能量需求。
