Doi Y, Ozaka T, Katsuki M, Fukushige H, Toyama E, Kanazawa Y, Arashidani K, Fujimoto S
Department of Anatomy, University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan.
Anat Rec. 1995 Jul;242(3):374-82. doi: 10.1002/ar.1092420310.
Endothelin-1 (ET-1) and sarafotoxin-S6b (STX) induce a remarkable degranulation of Weibel-Palade (WP) bodies prior to the vasocontraction of toad aortas. As WP bodies play the role of a reservoir site of the histamine in the endothelial cells, there is the possibility that ET-1 and STX evoke the release of histamine from WP bodies of this vessel.
Histamine concentrations were assayed by high-performance liquid chromatography (HPLC) from the perfusate after being perfused with a solution containing ET-1 and STX. Each vessel was fixed and embedded for conventional electron microscopy and immunoelectron microscopy using antihistamine sera.
The appreciable concentrations of histamine were assayed by HPLC from the perfusate after the toad aortas were perfused with a solution containing ET-1 and STX. The immunoelectron microscopy revealed that histamine immunoreactive gold particles in the WP bodies remarkably decreased in number in the treated samples when compared to the control ones. Our immunoelectron micrographs indicated that the release of histamine from the endothelial cells occurred in association with the degranulation and the exocytosis of the WP bodies after treatment with ET-1 and STX.
The present study clearly shows that ET-1 and STX induce the histamine release from WP bodies of the toad aortas by means of HPLC and immunoelectron microscopy. Histamine discharged from the WP bodies may be involved in the vasocontraction evoked by ET-1 and STX.
内皮素-1（ET-1）和芋螺毒素-S6b（STX）在蟾蜍主动脉血管收缩之前可诱导魏尔-帕拉德小体（WP小体）显著脱颗粒。由于WP小体在内皮细胞中起着组胺储存位点的作用，因此ET-1和STX有可能引起该血管WP小体中组胺的释放。
在用含有ET-1和STX的溶液灌注后，通过高效液相色谱法（HPLC）测定灌注液中的组胺浓度。将每个血管固定并包埋，用于常规电子显微镜检查和使用抗组胺血清的免疫电子显微镜检查。
在用含有ET-1和STX的溶液灌注蟾蜍主动脉后，通过HPLC测定出灌注液中存在可观浓度的组胺。免疫电子显微镜显示，与对照样品相比，处理过的样品中WP小体内组胺免疫反应性金颗粒的数量显著减少。我们的免疫电子显微镜照片表明，在用ET-1和STX处理后，组胺从内皮细胞的释放与WP小体的脱颗粒和胞吐作用有关。
本研究通过HPLC和免疫电子显微镜清楚地表明，ET-1和STX可诱导蟾蜍主动脉WP小体释放组胺。从WP小体释放的组胺可能参与了ET-1和STX引起的血管收缩。
