Analyses of vasoactive peptides released from the vascular endothelial cells

1)用组胺释放剂化合物48/80作用于培养的人脐静脉内皮细胞，检测到两种肽（20 k和30 k）从韦伯-帕拉德小体（WP）中释放出来。由于这些肽不是从WP未脱颗粒的对照样品中获得的，2）在同一切片上用免疫电子显微镜双标记技术显示，人脐静脉内皮细胞的WP同时显示组胺和von willebrand因子的定位。给予内皮素-1和sarafotoxin-S6 b后的离体蟾蜍粪便。将这两种药物单剂量（10-^8M）应用于保存内皮的血管和微血管，在给药2 min后诱导内皮依赖性血管收缩，并且在2 min内WP的超微结构变化如脱颗粒和内容物通过胞吐排出变得明显。这表明WP含有这两种药物释放的血管收缩肽。

1) Release of two kinds of peptides (20k and 30k) were detected from Weibel-Palade bodies (WP) in the cultured endothelial cells of the full term human umbilical veins after administration of compound 48/80, a histamine releaser. Since these peptides were not obtained from control samples which WP is not degranulated, they are considered to be derived from WP.2) The immunoelectron microscopy using the double-immunolabeling technique on the same ultrathin section revealed that WP of the human umbilical vein endothelial cells shows simultaneous localizations of histamine and von willebrand factor.3) Dose-dependent tension curves were recorded from the in-vitro toad aortar after administration of endothelin-1 and sarafotoxin-S6b. By a single dose application (10-^8M) of these two drugs to both endothelium-preserved and venuded vessels, the induction of the endothelium-dependent vasocontraction occurs after 2 min of administration, and the ultrastructural changes of WP such as degranulation and expulsion of their contents by exocytosis become evident within 2 min. This indicates that WP contains vasocontractile peptides released by these two drugs.