Baker H, Frank O, DeAngelis B, Baker E R
Department of Preventive Medicine, New Jersey Medical School, Newark.
Int J Vitam Nutr Res. 1993;63(1):22-6.
Changes of short-chain (free) and long-chain (acyl) carnitine activity (CA) in plasma, whole blood, red blood cells (rbc) and urine were induced (a) by ingestion of L-carnitine as a single dose of 500 mg, or 2500 mg, or (b) by ingestion of a daily dose of 2500 mg for 10 days. A single 500-mg dose induced insignificant increases of CA in blood constituents. However elevated free CA was noted in urine. Single or daily high doses--e.g. 2500 mg of carnitine--significantly increased free and acyl-CA in plasma, whole blood and urine, but these increases were low. Variations in dosage or frequency of carnitine intake led to no changes in rbc CA; presumably CA in plasma diffused only slowly into rbc. The apparent low absorption of carnitine suggests that oral therapy may not effect rapid repletion of body stores of CA.
通过以下方式诱导血浆、全血、红细胞（rbc）和尿液中短链（游离）和长链（酰基）肉碱活性（CA）的变化：（a）单次摄入500毫克或2500毫克L-肉碱；或（b）连续10天每天摄入2500毫克。单次500毫克剂量导致血液成分中CA的增加不显著。然而，尿液中游离CA升高。单次或每日高剂量——例如2500毫克肉碱——显著增加血浆、全血和尿液中的游离和酰基CA，但这些增加幅度较小。肉碱摄入量或摄入频率的变化不会导致红细胞CA的改变；推测血浆中的CA仅缓慢扩散到红细胞中。肉碱明显的低吸收率表明口服治疗可能无法迅速补充体内CA储备。
