Hollister A S, Breese G R, Kuhn C M, Cooper B R, Schanberg S M
J Pharmacol Exp Ther. 1976 Jul;198(1):12-22.
Locomotor activity induced by d-amphetamine was found to be potentiated by food deprivation, a tryptophan-free diet, p-chlorophenylalanine and drugs proposed to antagonize serotonin receptors in brain. Administration of L-tryptophan 1 hour prior to d-amphetamine injection was found to antagonize the enhanced response to d-amphetamine in starved rats and in rats which had tryptophan removed from their diet. However, tryptophan did not block the potentiated response to d-amphetamine in animals pretreated with p-chlorophenylalanine. These findings suggested that the antagonism of d-amphetamine-induced activity by tryptophan in starved rats and rats fed a tryptophan-free diet was not due to a nonspecific depressant effect of the amino acid. Since accumulation of d-amphetamine and its metabolites was not affected by any of the treatments which enhanced its activity, it seems unlikely that an alteration in the metabolism of d-amphetamine can explain these findings. The present work provides additional support for the view that serotonergic fibers play an important role in the actions of d-amphetamine.
研究发现，食物剥夺、无色氨酸饮食、对氯苯丙氨酸以及被认为可拮抗脑内5-羟色胺受体的药物，均可增强右旋苯丙胺诱发的运动活性。在注射右旋苯丙胺前1小时给予L-色氨酸，可拮抗饥饿大鼠和饮食中去除色氨酸的大鼠对右旋苯丙胺增强的反应。然而，色氨酸并不能阻断用对氯苯丙氨酸预处理的动物对右旋苯丙胺增强的反应。这些发现表明，色氨酸对饥饿大鼠和喂食无色氨酸饮食大鼠中右旋苯丙胺诱发活性的拮抗作用，并非由于该氨基酸的非特异性抑制作用。由于右旋苯丙胺及其代谢产物的蓄积不受任何增强其活性的处理的影响，因此右旋苯丙胺代谢的改变似乎无法解释这些发现。目前的研究工作为5-羟色胺能纤维在右旋苯丙胺作用中起重要作用的观点提供了更多支持。
