title: Evaluation of blood-brain barrier permeability in tryptophan hydroxylase 2-knockout mice.
abstract: 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.
authors.affiliation: Department of Histology and Embryology, Institute of Neuroscience, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China.
authors.forename: Chao-Jin
authors.initials: CJ
authors.lastname: Xu
authors.affiliation: Department of Anatomy, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China.
authors.lastname: Peng-Zhang
authors.affiliation: Department of Histology and Embryology, Institute of Neuroscience, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China.
authors.forename: Ting-Li
authors.initials: TL
authors.lastname: Dai
authors.affiliation: Department of Histology and Embryology, Institute of Neuroscience, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China.
authors.forename: Xue-Yuan
authors.initials: XY
authors.lastname: Niu
authors.affiliation: School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China.
authors.forename: Jun-Ling
authors.initials: JL
authors.lastname: Wang
authors.affiliation: Department of Histology and Embryology, Institute of Neuroscience, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China.
authors.forename: Ming-Shun
authors.initials: MS
authors.lastname: Jin
authors.affiliation: Department of Histology and Embryology, Institute of Neuroscience, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China.
authors.lastname: Min-Liao
keywords: 5-hydroxytryptamine; blood-brain barrier; tryptophan hydroxylase 2