Igisu H, Matsuoka M, Iryo Y
Department of Environmental Toxicology, University of Occupational and Environmental Health, Kitakyushu, Japan.
Sangyo Eiseigaku Zasshi. 1995 Mar;37(2):75-82. doi: 10.1539/sangyoeisei.37.2_75.
Carnitine (beta-hydroxy-gamma-trimethylammonium butyrate) is widely distributed in the body including the nervous system. Its physiological function, viz. a carrier of long-chain fatty acids through the inner mitochondrial membrane, has been well established. In this review, mainly based on our experiments, we discuss the possibility that carnitine may have effects other than the "physiological" function and that it may be a potent protector of the brain. When mice were exposed to ammonia (intraperitoneal injection of ammonium acetate), they developed seizures and concentrations of brain energy metabolites were altered; ATP and phosphocreatine decreased while ADP, AMP, pyruvate and lactate increased. The seizures and changes in brain energy metabolites were clearly suppressed when the mice were pre-treated with carnitine. Furthermore, changes in energy metabolites in the brain caused by severe ischemia (decapitation) were also suppressed by carnitine. Since D-carnitine showed similar effects as those of L-carnitine, the effects seem due to function(s) of carnitine yet to be defined. Intrinsic substances including carnitine appear to deserve further studies for possible use in protecting the brain.
肉碱（β-羟基-γ-三甲基铵丁酸）广泛分布于包括神经系统在内的体内。其生理功能，即作为长链脂肪酸通过线粒体内膜的载体，已得到充分证实。在本综述中，主要基于我们的实验，我们讨论了肉碱可能具有“生理”功能以外的作用且可能是大脑有力保护剂的可能性。当小鼠暴露于氨（腹腔注射醋酸铵）时，它们会发生惊厥且脑能量代谢物浓度会发生改变；三磷酸腺苷（ATP）和磷酸肌酸减少，而二磷酸腺苷（ADP）、一磷酸腺苷（AMP）、丙酮酸和乳酸增加。当小鼠用肉碱预处理时，惊厥及脑能量代谢物的变化明显受到抑制。此外，肉碱也抑制了由严重缺血（断头）引起的脑能量代谢物变化。由于D-肉碱显示出与L-肉碱相似的作用，这些作用似乎归因于肉碱尚未明确的功能。包括肉碱在内的内源性物质似乎值得进一步研究以探讨其在保护大脑方面的潜在用途。
