Institute for Experimental Surgery, University of Rostock, Rostock, Germany.
Surgery. 2012 Jan;151(1):26-36. doi: 10.1016/j.surg.2011.06.026. Epub 2011 Oct 22.
In the early postoperative period after pancreas-kidney transplantation, pancreatic venous thrombosis is a major complication that leads to allograft dysfunction and graft loss. Beside ischemia and reperfusion injury, immunosuppressive drugs have been accused of supporting thrombogenicity. The aim of this study was to evaluate the effect of commonly applied immunosuppressants on microvascular thrombus formation in normal and postischemic tissue in vivo.
In the skin fold chambers of tacrolimus-, cyclosporine A-, antithymocyte globulin-, rapamycine-, or saline-treated mice, light/dye-induced microvascular thrombus formation was studied. Additional mice underwent ischemia and reperfusion of the skin fold chamber tissue and received tacrolimus, antithymocyte globulin, or saline before reperfusion. Additionally, the effect of prednisolone was tested in animals with ischemia and reperfusion. Concentrations of sP-selectin, soluble vascular cell adhesion molecule-1, and asymmetric dimethylarginine were assessed by enzyme-linked immunosorbent assay. Immunohistochemistry of the skin fold chamber tissue served for analysis of vascular endothelial nitric oxide synthase and inducible nitric oxide synthase expression.
In normal tissue, tacrolimus, cyclosporine A, antithymocyte globulin, and rapamycine accelerated microvascular thrombus formation significantly when compared with saline. Whereas ischemia and reperfusion in saline-treated mice enhanced thrombus formation, thrombogenicity was not further increased by ischemia and reperfusion in tacrolimus- or antithymocyte globulin-treated animals. Application of prednisolone reversed the tacrolimus- and antithymocyte globulin-induced prothrombotic effect. Antithymocyte globulin increased sP-selectin and soluble vascular cell adhesion molecule-1, whereas tacrolimus induced asymmetric dimethylarginine production significantly. While tacrolimus and antithymocyte globulin additionally induced endothelial nitric oxide synthase and inducible nitric oxide synthase expression, cyclosporine A influenced only endothelial inducible nitric oxide synthase expression.
Immunosuppressants enhance thrombus formation in vivo. Although antithymocyte globulin activates the microvascular endothelium, we show for the first time that tacrolimus increases asymmetric dimethylarginine plasma levels. Thus, impaired nitric oxide availability might be the underlying mechanism for the tacrolimus-associated increased thrombogenicity. The efficacy of prednisolone to reverse the tacrolimus-associated and antithymocyte globulin-associated acceleration of thrombus formation underlines the application of this anti-inflammatory drug prior to reperfusion in immunosuppressive regimens.
在胰腺-肾脏移植后的早期术后阶段，胰腺静脉血栓形成是导致移植物功能障碍和移植物丢失的主要并发症。除了缺血再灌注损伤外，免疫抑制剂也被指责支持血栓形成。本研究的目的是评估常用免疫抑制剂对体内正常和缺血组织中小血管血栓形成的影响。
在他克莫司、环孢素 A、抗胸腺细胞球蛋白、雷帕霉素或生理盐水处理的小鼠的皮褶室中，研究光/染料诱导的微血管血栓形成。另外，一些小鼠接受皮褶室组织的缺血再灌注，并在再灌注前接受他克莫司、抗胸腺细胞球蛋白或生理盐水。此外，还在缺血再灌注的动物中测试了泼尼松龙的作用。通过酶联免疫吸附试验评估 sP-选择素、可溶性血管细胞黏附分子-1 和非对称性二甲基精氨酸的浓度。皮褶室组织的免疫组织化学用于分析血管内皮一氧化氮合酶和诱导型一氧化氮合酶的表达。
在正常组织中，与生理盐水相比，他克莫司、环孢素 A、抗胸腺细胞球蛋白和雷帕霉素明显加速了微血管血栓形成。虽然生理盐水处理的小鼠的缺血再灌注增强了血栓形成，但在他克莫司或抗胸腺细胞球蛋白处理的动物中，缺血再灌注并没有进一步增加血栓形成。泼尼松龙的应用逆转了他克莫司和抗胸腺细胞球蛋白诱导的促血栓形成作用。抗胸腺细胞球蛋白增加了 sP-选择素和可溶性血管细胞黏附分子-1 的水平，而他克莫司则显著诱导了非对称性二甲基精氨酸的产生。虽然他克莫司和抗胸腺细胞球蛋白还诱导了内皮一氧化氮合酶和诱导型一氧化氮合酶的表达，但环孢素 A仅影响内皮诱导型一氧化氮合酶的表达。
免疫抑制剂增强体内血栓形成。虽然抗胸腺细胞球蛋白激活了微血管内皮细胞，但我们首次表明，他克莫司增加了血浆中非对称性二甲基精氨酸的水平。因此，一氧化氮可用性的受损可能是他克莫司相关血栓形成增加的潜在机制。泼尼松龙在免疫抑制方案中再灌注前应用可逆转他克莫司相关和抗胸腺细胞球蛋白相关的血栓形成加速，这强调了这种抗炎药物的应用。
