Carter R B, Dykstra L A, Leander J D, Appel J B
Pharmacol Biochem Behav. 1978 Aug;9(2):249-53. doi: 10.1016/0091-3057(78)90172-7.
The effects of 5-hydroxytryptophan (5-HTP) were studied in rats trained to press a lever under a fixed-ratio (Fr-32) schedule of water presentation. d-, l-and d,l-5-HTP all decreased responding in a dose-related manner. The levo isomer (12.5-25 mg/kg) was twice as potent as the racemic form (25-50 mg/kg) in this respect. Moderate doses of d-5-HTP (less than 100 mg/kg) did not affect responding, whereas 200 mg/kg produced almost complete suppression. The response decrement produced by 25 mg/kg l-5-HTP was completely antagonized by pretreatment with either 50 mg/kg or 400 mg/kg of the decarboxylase inhibitor, benserazide (Ro4-4602). The specific peripheral decarboxylase inhibitor, carbidopa (MK-486) (50 mg/kg) and the peripheral serotonergic antagonist, xylamidine tosylate (1 mg/kg) also antagonized the effects of 25 mg/kg l-5-HTP. These results suggest that at least some of the behavioral effects of 5-HTP are due to increases in levels or turnover of 5-HTP in peripheral serotonergic neuronal systems.
在接受训练按固定比率（Fr - 32）程序获取水的大鼠中研究了5 - 羟色氨酸（5 - HTP）的作用。d -、l - 和d，l - 5 - HTP均以剂量相关的方式降低反应。在这方面，左旋异构体（12.5 - 25毫克/千克）的效力是消旋体（25 - 50毫克/千克）的两倍。中等剂量的d - 5 - HTP（低于100毫克/千克）不影响反应，而200毫克/千克几乎产生完全抑制。用50毫克/千克或400毫克/千克的脱羧酶抑制剂苄丝肼（Ro4 - 4602）预处理可完全拮抗25毫克/千克l - 5 - HTP产生的反应减少。特异性外周脱羧酶抑制剂卡比多巴（MK - 486）（50毫克/千克）和外周5 - 羟色胺能拮抗剂甲苯磺酸赛拉米定（1毫克/千克）也拮抗25毫克/千克l - 5 - HTP的作用。这些结果表明，5 - HTP的至少一些行为效应是由于外周5 - 羟色胺能神经元系统中5 - HTP水平或周转的增加所致。
