Department of Fisheries and Wildlife, College of Agricultural Sciences, Oregon State University, 104 Nash Hall, Corvallis, OR, USA.
Department of Fisheries and Wildlife, College of Agricultural Sciences, Oregon State University, 104 Nash Hall, Corvallis, OR, USA.
Fish Shellfish Immunol. 2018 Sep;80:655-659. doi: 10.1016/j.fsi.2018.06.038. Epub 2018 Jun 20.
When fish perceive stressful scenarios, their hypothalamus-pituitary-interrenal axis is activated resulting in the release of corticotropin releasing hormone, adrenocorticotropic hormone (ACTH), and finally cortisol. The physiologic stress response of fish has most often been linked to the reduced performance of the immune system, with a few exceptions where the immune system is activated. In this report, we tested the hypothesis that oxidative burst activity levels in juvenile Chinook salmon (Oncorhynchus tshawytscha) are altered when the fish is presented with a stressor. Fish were subjected to a stressor for 3 h and then allowed to recover for 20 h following the stressor. Plasma and spleens were collected from euthanized fish before the stressor, at the end of a 3 h stressor, and 23 h after the start of the experiment. Plasma was held at -80 °C until cortisol radioimmunoassay analysis was performed to confirm stress. Spleens were held in Dulbecco's Modified Eagle Medium overnight and analyzed the day following collection. Oxidative burst activity was measured in splenic leukocytes after being stimulated with phorbol 12-myristate 13-acetate. We found a significant increase in activated oxidative burst from fish subjected to the stressor as compared to unstressed fish. Speculation is given to ACTH being the leukocyte priming agent in this experiment rather than the cortisol itself.
当鱼类感知到压力情景时，其下丘脑-垂体-肾上腺轴会被激活，导致促肾上腺皮质释放激素、促肾上腺皮质激素（ACTH）的释放，最终导致皮质醇的释放。鱼类的生理应激反应通常与免疫系统功能下降有关，但也有少数例外情况，即免疫系统被激活。在本报告中，我们测试了一个假设，即当鱼类受到应激源刺激时，其幼鲑（Oncorhynchus tshawytscha）的活性氧爆发水平会发生变化。鱼被置于应激源下 3 小时，然后在应激源结束后 20 小时恢复。在应激前、3 小时应激结束时和实验开始后 23 小时从安乐死的鱼中采集血浆和脾脏。血浆在-80°C 下保存，直到进行皮质醇放射免疫分析以确认应激。脾脏在 Dulbecco's Modified Eagle Medium 中保存过夜，并在收集后的第二天进行分析。在脂多糖刺激后测量脾脏白细胞中的活性氧爆发活性。与未受应激的鱼相比，应激鱼的活性氧爆发明显增加。推测在本实验中，ACTH 是白细胞的启动剂，而不是皮质醇本身。
