Salzman S K, Hirofugi E, Knight P B, Llados-Eckman C, Beckman A L, Winokur A
Research Department, Alfred I. du Pont Institute, Wilmington, Delaware.
Cent Nerv Syst Trauma. 1987;4(3):181-96. doi: 10.1089/cns.1987.4.181.
The sites and mechanisms by which thyrotropin-releasing hormone (TRH) may ameliorate the effects of spinal cord contusion were studied in the rabbit. We have examined the actions of an effective intravenous TRH infusion on the spinal content and utilization of the monoamine neurotransmitters (norepinephrine [NE], dopamine [DA], and serotonin [5-HT]) in both control and injured animals. The ability of TRH to penetrate the blood-brain barrier was determined by the measurement of spinal cord TRH immunoreactivity and the effect of TRH upon the development of traumatic edema was evaluated. TRH was found to enter the spinal cord to a large extent in approximately half the animals, but to a lesser degree in the remainder. This indicates the potential for a central site of action. In this regard, TRH induced a significant increase in the metabolism or utilization of 5-HT above the injury site. This effect was not observed in control animals. Finally, TRH was able to cancel the formation of edema at the injury site. These results are correlated with previously described mechanisms and are discussed in terms of the co-existence of TRH and 5-HT in raphe-spinal neurons descending from the medulla.
我们在兔子身上研究了促甲状腺激素释放激素（TRH）改善脊髓挫伤影响的部位和机制。我们检测了有效静脉输注TRH对对照动物和受伤动物脊髓中去甲肾上腺素（NE）、多巴胺（DA）和5-羟色胺（5-HT）等单胺类神经递质含量及利用情况的作用。通过测量脊髓TRH免疫反应性来确定TRH穿透血脑屏障的能力，并评估TRH对创伤性水肿形成的影响。结果发现，大约一半的动物中TRH能大量进入脊髓，而其余动物中进入程度较小。这表明其存在中枢作用位点的可能性。在这方面，TRH使损伤部位上方的5-HT代谢或利用显著增加，对照动物中未观察到这种效应。最后，TRH能够消除损伤部位水肿的形成。这些结果与先前描述的机制相关，并根据延髓下行的中缝脊髓神经元中TRH和5-HT的共存进行了讨论。
