Gibson C J, Deikel S M, Young S N, Binik Y M
Psychopharmacology (Berl). 1982;76(2):118-21. doi: 10.1007/BF00435264.
Behaviour was observed in mice given L-tryptophan, L-tyrosine or L-phenylalanine and then placed either in an open field or in water in a narrow cylinder. Animals placed in water (swim test) soon assume a characteristic immobile posture. Most antidepressants, including pharmacologically atypical ones, decrease immobility in the swim test while many decrease or do not affect activity in the open field test. Tryptophan increased immobility in the swim test, but did not affect open field activity and thus did not exhibit the normal profile of activity for an antidepressant. Tyrosine decreased immobility in the swim test and markedly increased activity in the open field test, an action similar to the psychostimulants amphetamine and caffeine. Phenylalanine decreased immobility in the swim test, but did not affect open field activity. Thus, its behavioural effects are similar to those of an antidepressant. As expected, tryptophan increased brain tryptophan and serotonin in a dose-related fashion. Tyrosine did not alter dopamine or noradrenaline levels, while phenylalanine lowered dopamine, noradrenaline and serotonin. These biochemical data do not fully explain the behavioural results.
对给予L-色氨酸、L-酪氨酸或L-苯丙氨酸的小鼠进行行为观察，然后将它们置于旷场或狭窄圆筒中的水中。置于水中的动物（游泳试验）很快会呈现出一种特征性的不动姿势。大多数抗抑郁药，包括药理学上非典型的抗抑郁药，在游泳试验中会减少不动时间，而许多抗抑郁药在旷场试验中会减少或不影响活动。色氨酸在游泳试验中增加了不动时间，但不影响旷场活动，因此未表现出抗抑郁药正常的活性特征。酪氨酸在游泳试验中减少了不动时间，并在旷场试验中显著增加了活动，这一作用类似于精神兴奋剂苯丙胺和咖啡因。苯丙氨酸在游泳试验中减少了不动时间，但不影响旷场活动。因此，其行为效应与抗抑郁药相似。正如预期的那样，色氨酸以剂量相关的方式增加了脑内色氨酸和5-羟色胺水平。酪氨酸未改变多巴胺或去甲肾上腺素水平，而苯丙氨酸降低了多巴胺、去甲肾上腺素和5-羟色胺水平。这些生化数据并不能完全解释行为结果。
