Xu Chao-Jin, Dai Ting-Li, Niu Xue-Yuan, Wang Jun-Ling, Jin Ming-Shun
Department of Histology and Embryology, Institute of Neuroscience, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China.
Department of Anatomy, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China.
Exp Ther Med. 2014 Nov;8(5):1467-1470. doi: 10.3892/etm.2014.1938. Epub 2014 Aug 28.
The blood-brain barrier (BBB) is critical to the health of the central nervous system (CNS). The possibility that 5-hydroxytryptamine (5-HT) participates in the alteration of the BBB has been previously demonstrated. Tryptophan hydroxylase 2 (TPH2) is a unique genetic enzyme isoform that catalyzes the rate-limiting step in the biosynthesis of 5-HT in the CNS; however, its role in the permeability changes of the BBB remains unclear. In the present study, TPH2-knockout mice were utilized in the assessment of BBB disruption, as measured by the Evans Blue (EB) extravasation or fluorescein isothiocyanate-albumin leakage assay in the brain. EB was not found to be retained in the brain in the TPH2-knockout mice or the wild-type controls. The results of the study demonstrate that TPH2 knockout has no effect on BBB permeability, indicating that TPH2 and the 5-HT system in the CNS are not sufficient to influence the BBB leakage.
血脑屏障（BBB）对中枢神经系统（CNS）的健康至关重要。先前已证明5-羟色胺（5-HT）参与血脑屏障改变的可能性。色氨酸羟化酶2（TPH2）是一种独特的基因酶亚型，可催化中枢神经系统中5-HT生物合成的限速步骤；然而，其在血脑屏障通透性变化中的作用仍不清楚。在本研究中，通过伊文思蓝（EB）外渗或脑内异硫氰酸荧光素-白蛋白泄漏试验来评估血脑屏障破坏情况，使用了TPH2基因敲除小鼠。在TPH2基因敲除小鼠或野生型对照中均未发现EB滞留在脑内。研究结果表明，TPH2基因敲除对血脑屏障通透性没有影响，这表明中枢神经系统中的TPH2和5-HT系统不足以影响血脑屏障渗漏。
