Braganza A, Wilson W O
J Appl Physiol Respir Environ Exerc Physiol. 1978 Nov;45(5):705-8. doi: 10.1152/jappl.1978.45.5.705.
Endogenous level and turnover of brain norepinephrine (NE), epinephrine (E), dopamine (DA), and serotonin (5-HT) in male Japanese quail were determined after acute (6 h) and chronic (5 wk) exposure to thermal (34 degrees C) and cyclic temperature (10--34 degrees C) stress. alpha-Methyl-p-tyrosine (alpha-MT) and p-chlorophenylalanine (PCPA) were used to study the turnover of the monoamine levels. The differences between the monoamine levels of drug-treated birds and control (22 degrees C) birds were regarded as changes in turnover. High ambient temperature (34 degrees C) stress for 6 h increased brain NE turnover. However, chronic exposure (5 wk) to 34 degrees C, and to cyclic temperatures (10--34 degrees C), did not increase turnover of brain NE. Also, acute and chronic heat exposures did not significantly change E turnover. High acute temperature stress had no effect on brain DA turnover, although chronic exposure of birds to 34 and 10--34 degrees C resulted in a retarded turnover. The central 5-HT turnovers increased when birds were subjected to acute 34 degrees C stress. Five weeks of exposure to 34 and 10--34 degrees C caused declines in 5-HT turnovers. Thus, the results indicate that NE and 5-HT turnovers increase during acute thermal exposure, but acclimation to thermal stress for 5 wk reduces the turnover of brain NE, 5-HT, and DA.
在雄性日本鹌鹑急性（6小时）和慢性（5周）暴露于热应激（34摄氏度）和循环温度应激（10 - 34摄氏度）后，测定了其大脑中去甲肾上腺素（NE）、肾上腺素（E）、多巴胺（DA）和5-羟色胺（5-HT）的内源性水平及更新率。使用α-甲基对酪氨酸（α-MT）和对氯苯丙氨酸（PCPA）来研究单胺水平的更新率。将药物处理组鸟类和对照组（22摄氏度）鸟类的单胺水平差异视为更新率的变化。6小时的高环境温度（34摄氏度）应激增加了大脑NE的更新率。然而，慢性暴露（5周）于34摄氏度以及循环温度（10 - 34摄氏度）并未增加大脑NE的更新率。此外，急性和慢性热暴露均未显著改变E的更新率。高急性温度应激对大脑DA更新率无影响，尽管鸟类慢性暴露于34摄氏度和10 - 34摄氏度会导致更新率减缓。当鸟类受到急性34摄氏度应激时，中枢5-HT更新率增加。暴露于34摄氏度和10 - 34摄氏度5周会导致5-HT更新率下降。因此，结果表明，急性热暴露期间NE和5-HT更新率增加，但适应热应激5周会降低大脑NE、5-HT和DA的更新率。
