Huang Yanming, Wang Lan, Verweire Ineke, Qiang Beiping, Liu Xiaoshun, Verbeken Erik, Schacht Etienne, De Scheerder Ivan
Department of Cardiology, University Hospital Gasthuisberg, Leuven, Belgium.
J Invasive Cardiol. 2002 Sep;14(9):505-13.
Polymer coating can optimize the surface characteristics of metallic coronary stents and serve as a vehicle for local drug delivery. Major problems, however, include the lack of biocompatibility of the polymers used and the limited amount of drug that can be loaded onto the stent. Stainless-steel stents were spray-coated or spray-coated combined with a barrier coating using a fluorinated polymethacrylate PFM-P75 impregnated with different methylprednisolone concentrations. When spray-coated with highly concentrated methylprednisolone ( 33%) fluorinated polymethacrylate PFM-P75, the surface became progressively more rough. Adding a barrier coating, however, could decrease these surface irregularities of methylprednisolone-loaded PFM-P75 spray-coated stents. In vitro, most of the methylprednisolone was released in the first 48 hours. A barrier coating could dramatically slow down the drug release from 80% to 13% during the first 48 hours. Histomorphometric analysis showed that the inflammatory response and neointimal hyperplasia of methylprednisolone-loaded stents were lower than in control stents. Neointimal hyperplasia of methylprednisolone-loaded PFM-P75 stents spray-coated with a barrier coating was decreased compared to the non-barrier-coated methylprednisolone-loaded stents. In conclusion, spray coating enables the use of high methylprednisolone concentrations. A barrier coating could significantly slow down the methylprednisolone release. Methylprednisolone-loaded PFM-P75-coated stents could significantly inhibit the inflammatory response and neointimal hyperplasia. The response to methylprednisolone was related to the dose used and the release time of the drug.
聚合物涂层可以优化金属冠状动脉支架的表面特性，并作为局部药物递送的载体。然而，主要问题包括所用聚合物缺乏生物相容性以及可加载到支架上的药物量有限。不锈钢支架采用含不同甲基泼尼松龙浓度的氟化聚甲基丙烯酸酯PFM-P75进行喷涂或喷涂并结合阻隔涂层。当用高浓度甲基泼尼松龙（33%）的氟化聚甲基丙烯酸酯PFM-P75进行喷涂时，表面变得越来越粗糙。然而，添加阻隔涂层可以减少载有甲基泼尼松龙的PFM-P75喷涂支架的这些表面不规则性。在体外，大部分甲基泼尼松龙在最初48小时内释放。阻隔涂层可以在最初48小时内将药物释放从80%显著减慢至13%。组织形态计量学分析表明，载有甲基泼尼松龙的支架的炎症反应和内膜增生低于对照支架。与未涂阻隔涂层的载有甲基泼尼松龙的支架相比，涂有阻隔涂层的载有甲基泼尼松龙的PFM-P75支架的内膜增生减少。总之，喷涂能够使用高浓度的甲基泼尼松龙。阻隔涂层可以显著减慢甲基泼尼松龙的释放。载有甲基泼尼松龙的PFM-P75涂层支架可以显著抑制炎症反应和内膜增生。对甲基泼尼松龙的反应与所用剂量和药物释放时间有关。
