Possible relationship between polyamines and traumatic stress: Changes in polyamine levels after weter-immesdion restraint stress in mouse brain

其他人和我们之前的研究表明，癫痫脑中的神经元应激和损伤显著改变了多胺代谢，导致腐胺水平显著升高。最近，也有报道称，创伤应激改变了脑多胺代谢，可能与情感障碍有关。在本研究中，我们检测了施加水浸束缚应激后大鼠额叶皮质、海马体、下丘脑和血浆中多胺的水平，以进一步阐明多胺与创伤应激的关系。应激小鼠被限制在束缚应激笼中，浸泡在保持在25℃的水中2小时。应激结束后5min、6h、24h、48h断头处死动物。在应激作用后24小时，大脑所有部位的腐胺水平均显著升高。应激后6小时和24小时，额叶皮质和下丘脑的精胺和精胺水平无明显变化或略有下降。在血浆中，多胺水平在应激作用后的任何时间间隔内都没有变化。在束缚应激而不浸水的情况下，腐胺水平仅在额叶皮质增加。预先给予安定(5 mg/kg，i.p)。减少应激诱导的多胺变化。这些结果表明，多胺代谢的改变与创伤应激有关，其程度似乎与应激源的强度有关。

Previous studies, by others and by us, have shown that neuronal stress and injury in the epileptic brain significantly alter polyamine metabolism, resulting in a marked elevation of the putrescine level. Recently, it was also reported that brain polyamine metabolism is modified by traumatic stress and may be involved in affective disorders. In this study, we measured the polyamine levels in the frontal cortex, hippocampus, hypothalamus, and plasma after applying water-immersion restraint stress, to further clarify the relationship between polyamines and traumatic stress. To stress mice, they were confined in a restraint stress-cage and immersed in water maintained at 25℃ for 2h. The animals were decapitated 5min, 6h, 24h and 48h after the cessation of stress. In all parts of the brain, the putrescine levels were significantly elevated 24h after stress application. The spermidine and spermine levels were unchanged or slightly reduced in the frontal cortex and hypothalamus 6h and 24h after stress application. In the plasma, there is no change in polyamine levels at any time intervals after stress application. In the case of restraint stress without water-immersion, putrescine level was increased only in the frontal cortex. Pretreatment with diazepam (5mg/kg, i. p.) reduced the stress-induced polyamine changes. These results indicate that the change of polyamine metabolism is linked to traumatic stress and its magnitude appears to be related to the intensity of the stressor.