Chédotal A, Hamel E
Laboratory of Cerebrovascular Research, Montreal Neurological Institute, Que., Canada.
Neurosci Lett. 1990 Aug 24;116(3):269-74. doi: 10.1016/0304-3940(90)90085-n.
Nerve fibers synthesizing 5-hydroxytryptamine (5-HT or serotonin) were demonstrated in rat and cat cerebral blood vessels by immunohistochemical localization of the rate-limiting enzyme catalyzing the biosynthesis of 5-HT, namely tryptophan-5-hydroxylase (TPOH). TPOH-immunoreactive fibers were present in all parts of the circle of Willis with a somewhat less intense distribution in the vertebro-basilar segment. Single, small nerve fibers intermingled around the vessel wall were found in both species but clear TPOH-immunoreactive varicosities were observed predominantly in the rat. The most striking observation was the dense network of TPOH-positive fibers innervating some but not all small pial arteries, and, to a lesser extent, pial arterioles. These results provide the evidence that, at least in these species, the cerebrovascular bed is innervated by authentic serotonergic fibers which can synthesize their own 5-HT.
通过对催化5-羟色胺（5-HT或血清素）生物合成的限速酶，即色氨酸-5-羟化酶（TPOH）进行免疫组织化学定位，在大鼠和猫的脑血管中证实了合成5-羟色胺的神经纤维。TPOH免疫反应性纤维存在于 Willis 环的所有部位，在椎基底动脉段的分布强度稍低。在这两个物种中均发现单根小神经纤维在血管壁周围交织，但主要在大鼠中观察到清晰的TPOH免疫反应性膨体。最引人注目的观察结果是，TPOH阳性纤维形成密集网络，支配部分而非全部软膜小动脉，并在较小程度上支配软膜小动脉。这些结果证明，至少在这些物种中，脑血管床由能够合成自身5-羟色胺的真正5-羟色胺能纤维支配。
