Joseph M H, Kennett G A
Psychopharmacology (Berl). 1983;79(1):79-81. doi: 10.1007/BF00433020.
Prior administration of valine to rats has been shown previously to prevent restraint stress-induced increases in brain tryptophan and 5HT turnover. The present study demonstrates that the accompanying attenuation of the corticosteroid response to this stress is substantially reversed by administration of tryptophan with the valine. Tyrosine is not effective in reversing this attenuation, and in fact itself attenuates the corticosteroid response to the stress when given alone. It is concluded that at least part of the corticosteroid response to restraint stress is mediated by an increase in serotonergic activity that is dependent on increased supply of the precursor, tryptophan, and that this can be antagonised by either of two amino acids which compete with tryptophan for access to the brain. Implications for stress-associated human disorders are discussed.
先前的研究表明，给大鼠预先施用缬氨酸可防止束缚应激诱导的脑内色氨酸和5-羟色胺（5HT）代谢率升高。本研究表明，在给予缬氨酸的同时给予色氨酸，可显著逆转伴随而来的皮质类固醇对这种应激反应的减弱。酪氨酸在逆转这种减弱方面无效，事实上，单独给予酪氨酸时，它本身会减弱皮质类固醇对该应激的反应。得出的结论是，至少部分皮质类固醇对束缚应激的反应是由血清素能活性增加介导的，这种增加依赖于前体色氨酸供应的增加，并且这可以被两种与色氨酸竞争进入大脑的氨基酸中的任何一种所拮抗。文中讨论了对与应激相关的人类疾病的影响。
