Hietala P, Lindén I B, Grönfors N
J Pharm Pharmacol. 1979 Apr;31(4):205-8. doi: 10.1111/j.2042-7158.1979.tb13479.x.
In the rat, administration of 3-(3,4-dihydroxy)-L-phenylalanine (L-dopa) simultaneously with the corresponding alpha-keto acid, 3,4-dihydroxyphenylpyruvic acid (DHPPA), gives significantly higher concentrations of L-dopa in the serum and of dopamine and homovanillic acid in the brain than the same dose of L-dopa alone. Correspondingly, DHPPA potentiates the effect of L-dopa on the locomotor activity in reserpine-treated mice. DHPPA is postulated to increase the absorption of intact L-dopa from the gut by preventing the transamination reaction between L-dopa and the physiological alpha-keto acids.
在大鼠中，将3-(3,4-二羟基)-L-苯丙氨酸（L-多巴）与相应的α-酮酸3,4-二羟基苯丙酮酸（DHPPA）同时给药，血清中L-多巴以及脑中多巴胺和高香草酸的浓度显著高于单独给予相同剂量的L-多巴。相应地，DHPPA增强了L-多巴对利血平处理小鼠运动活性的影响。据推测，DHPPA通过阻止L-多巴与生理性α-酮酸之间的转氨反应来增加完整L-多巴从肠道的吸收。
