Trulson M E, Crisp T
Eur J Pharmacol. 1984 Apr 6;99(4):313-24. doi: 10.1016/0014-2999(84)90138-9.
Chronic administration of amphetamine to cats (twice daily, in doses increasing from 5 to 15 mg/kg over a 10-day period) elicited a number of behaviors e.g., limb flicking, abortive grooming, and excessive head shaking, which were originally proposed as an animal behavioral model for studying the actions of hallucinogens that depress central serotonergic neurotransmission. This drug treatment produced large decreases (approximately 50%) in central nervous system serotonin (5HT) and its major metabolite, 5-hydroxyindoleacetic acid, and even larger decreases (approximately 90%) in the levels of dopamine (DA) and norepinephrine. Administration of the 5HT precursors L-tryptophan (25 mg/kg i.p.) or L-5-hydroxytryptophan (12.5 mg/kg i.p.), a direct-acting 5HT agonist (quipazine, 1 mg/kg i.p.) or a monoamine oxidase inhibitor (tranylcypromine, 4 mg/kg i.p.) produced no significant changes in these behaviors in cats treated chronically with amphetamine. Administration of a 5HT reuptake blocker (fluoxetine, 5 mg/kg i.p.) produced a small, but significant, decrease in the frequency of occurrence of these behaviors in amphetamine-treated cats. L-Dihydroxyphenylalanine (L-DOPA, 20 mg/kg i.p.) greatly potentiated these behaviors in cats chronically treated with amphetamine, but L-DOPA was totally ineffective in eliciting these behaviors in naive animals. The behavioral effects of apomorphine (2 mg/kg i.p.) were also significantly potentiated by chronic amphetamine pretreatment. The amino acid precursor of DA, L-tyrosine (25 mg/kg i.p.), and a DA reuptake blocker, bupropion (5 mg/kg i.p.) were without significant effect on these behaviors in amphetamine-treated cats. The data suggest that these cat behaviors are elicited by an action at central DA receptors and that these receptors become supersensitive following chronic amphetamine administration. Furthermore, there may be a qualitative change in DA receptors, since L-DOPA is very effective in potentiating these behaviors in cats treated chronically with amphetamine, but is totally ineffective in naive cats.
对猫长期给予苯丙胺（每天两次，在10天内剂量从5毫克/千克增加到15毫克/千克）引发了一些行为，例如肢体轻弹、未遂梳理行为和过度摇头，这些行为最初被提议作为一种动物行为模型，用于研究抑制中枢5-羟色胺能神经传递的致幻剂的作用。这种药物治疗使中枢神经系统中5-羟色胺（5HT）及其主要代谢产物5-羟吲哚乙酸大幅减少（约50%），使多巴胺（DA）和去甲肾上腺素水平减少得更多（约90%）。给予5HT前体L-色氨酸（25毫克/千克腹腔注射）或L-5-羟色氨酸（12.5毫克/千克腹腔注射）、一种直接作用的5HT激动剂（喹哌嗪，1毫克/千克腹腔注射）或一种单胺氧化酶抑制剂（反苯环丙胺，4毫克/千克腹腔注射），对长期用苯丙胺治疗的猫的这些行为没有产生显著变化。给予一种5HT再摄取阻滞剂（氟西汀，5毫克/千克腹腔注射），使在用苯丙胺治疗的猫中这些行为出现的频率有小幅但显著的降低。L-二羟基苯丙氨酸（L-DOPA，20毫克/千克腹腔注射）极大地增强了长期用苯丙胺治疗的猫的这些行为，但L-DOPA在未用药的动物中完全无法引发这些行为。阿扑吗啡（2毫克/千克腹腔注射）的行为效应也因长期苯丙胺预处理而显著增强。DA的氨基酸前体L-酪氨酸（25毫克/千克腹腔注射）和一种DA再摄取阻滞剂安非他酮（5毫克/千克腹腔注射），对在用苯丙胺治疗的猫的这些行为没有显著影响。数据表明，这些猫的行为是由中枢DA受体的作用引发的，并且这些受体在长期给予苯丙胺后变得超敏。此外，DA受体可能存在质的变化，因为L-DOPA在增强长期用苯丙胺治疗的猫的这些行为方面非常有效，但在未用药的猫中完全无效。
