Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
Endoscopy. 2012 Sep;44(9):825-31. doi: 10.1055/s-0032-1309881. Epub 2012 Jul 2.
Metal stents for malignant biliary obstruction are susceptible to occlusion by tumor ingrowth or overgrowth. Therefore, we previously reported our use of a metal stent covered with a paclitaxel-incorporated membrane giving an antitumor effect to prevent occlusion from tumor ingrowth. We have also developed a new generation of paclitaxel-eluting biliary stent using a membrane containing Pluronic F-127 for effective drug delivery. The aim of this study was to investigate the safety and efficacy of drug delivery for this newly developed stent in the biliary tract.
Metal stents were coated with paclitaxel and various concentrations of Pluronic F-127 in phosphate-buffered saline solution. Stents containing varying concentrations were placed in the bile ducts of eight pigs divided as follows: group I, 0% Pluronic + 0% paclitaxel; group II, 0% Pluronic + 10% paclitaxel; group III, 10% Pluronic + 10% paclitaxel; group IV, 20% Pluronic + 10% paclitaxel. The histology of the porcine bile duct and the amount of paclitaxel in the porcine serum were examined. The amount of paclitaxel released was also measured in vitro.
Histologic changes in the porcine biliary epithelium were acceptable in terms of safety, based on inflammatory cell infiltration and fibrotic reaction. No significant differences in histology were observed between the groups. In the porcine serum analysis, released paclitaxel was detected for 28 days with the 10% Pluronic concentration (group III). However, released paclitaxel was observed for only 7 days in groups II and IV. In the in vitro experiments, long-lasting release of paclitaxel was also noted from the stent with 10% Pluronic.
The new paclitaxel-eluting stent with 10% Pluronic F-127 is safe and provides enhanced local drug delivery.
恶性胆道梗阻的金属支架容易被肿瘤向内生长或过度生长所阻塞。因此，我们之前报告了使用一种被紫杉醇包被的金属支架，以提供抗肿瘤作用来防止肿瘤向内生长引起的阻塞。我们还开发了一种使用含有 Pluronic F-127 的膜的新一代紫杉醇洗脱胆道支架，以实现有效的药物输送。本研究旨在探讨这种新开发的支架在胆道中药物输送的安全性和有效性。
将紫杉醇和不同浓度的 Pluronic F-127 涂覆在金属支架上，置于磷酸盐缓冲液中。将含有不同浓度的支架分别置于 8 头猪的胆管中，分为以下几组：I 组，0% Pluronic + 0%紫杉醇；II 组，0% Pluronic + 10%紫杉醇；III 组，10% Pluronic + 10%紫杉醇；IV 组，20% Pluronic + 10%紫杉醇。检查猪胆管的组织学和猪血清中的紫杉醇含量。还在体外测量紫杉醇的释放量。
根据炎症细胞浸润和纤维反应，猪胆管的组织学变化在安全性方面是可以接受的。各组之间的组织学无明显差异。在猪血清分析中，用 10% Pluronic 浓度（III 组）可检测到 28 天释放的紫杉醇。然而，在 II 组和 IV 组中仅观察到 7 天释放的紫杉醇。在体外实验中，还观察到含有 10% Pluronic 的支架具有长效的紫杉醇释放。
含有 10% Pluronic F-127 的新型紫杉醇洗脱支架安全且可增强局部药物输送。
