Lewis D A, Lowell R C, Cambria R A, Roche P C, Gloviczki P, Miller V M
Department of Surgery, Mayo Clinic and Foundation, Rochester, MN 55905, USA.
J Vasc Surg. 1997 Jan;25(1):187-97. doi: 10.1016/s0741-5214(97)70337-9.
Experiments were designed to determine whether endothelium isolated from adipose tissue and sodded onto expanded polytetrafluoroethylene grafts release endothelium-derived vasoactive factors.
Thin-walled expanded polytetrafluoroethylene grafts (6 mm internal diameter, 6 cm length, 30 microm pore size), one sodded with autogenous endothelial cells, the other unsodded, were implanted bilaterally in carotid arteries of 30 male mongrel dogs. Dogs were treated with 325 mg aspirin daily. After 6 weeks grafts were excised and perfused in a bioassay system. Effluent from the grafts stimulated with either acetylcholine, thrombin, adenosine 5-diphosphate, or the calcium ionophore A23187 was superfused over rings of canine femoral arteries without endothelium contracted with phenylephrine. Effluent from the grafts was analyzed by radioimmunoassay for thromboxane B2, 6-keto-prostaglandin F1alpha, endothelin-1, and C-type natriuretic peptide.
Ninety percent of the sodded grafts and 87% of the unsodded grafts were patent after 6 weeks. Bioassay rings superfused with effluent from sodded grafts stimulated with acetylcholine relaxed significantly more than rings superfused with effluent from similarly stimulated unsodded grafts. Biochemical analysis of the effluent showed an increase in 6-keto prostaglandin F1alpha and C-type natriuretic peptide and a decrease in endothelin-1 and thromboxane B2 release from the sodded compared with the unsodded grafts. Scanning electron microscopy showed a continuous layer of endothelial cells lining only the sodded grafts. Staining for alpha-actin and heavy-chain myosin showed a differentiated layer of smooth muscle below the endothelial layer on the sodded grafts. Finally, there was positive staining for C-type natriuretic peptide and endothelin-1 in the endothelium of the sodded grafts.
These results indicate that endothelial cells of sodded expanded polytetrafluoroethylene grafts produce endothelium-derived vasoactive factors. In addition, receptor-coupled synthesis/release of these factors is retained in sodded endothelial cells.
设计实验以确定从脂肪组织分离并铺覆于膨体聚四氟乙烯移植物上的内皮细胞是否释放内皮源性血管活性因子。
将薄壁膨体聚四氟乙烯移植物（内径6mm，长度6cm，孔径30μm），一个铺覆自体内皮细胞，另一个未铺覆，双侧植入30只雄性杂种犬的颈动脉。犬每日接受325mg阿司匹林治疗。6周后切除移植物并在生物测定系统中进行灌注。用乙酰胆碱、凝血酶、腺苷5-二磷酸或钙离子载体A23187刺激移植物后的流出物，灌注于用去氧肾上腺素预收缩的无内皮犬股动脉环上。通过放射免疫分析法分析移植物流出物中的血栓素B2、6-酮-前列腺素F1α、内皮素-1和C型利钠肽。
6周后，90%的铺覆移植物和87%的未铺覆移植物保持通畅。用乙酰胆碱刺激铺覆移植物后的流出物灌注的生物测定环，其舒张程度明显大于用同样刺激的未铺覆移植物后的流出物灌注的环。流出物的生化分析显示，与未铺覆移植物相比，铺覆移植物释放的6-酮-前列腺素F1α和C型利钠肽增加，内皮素-1和血栓素B2减少。扫描电子显微镜显示仅铺覆移植物内衬有连续的内皮细胞层。α-肌动蛋白和重链肌球蛋白染色显示铺覆移植物内皮细胞层下方有一层分化的平滑肌。最后，可以看到铺覆移植物的内皮细胞中C型利钠肽和内皮素-1呈阳性染色。
这些结果表明，铺覆膨体聚四氟乙烯移植物的内皮细胞产生内皮源性血管活性因子。此外，这些因子的受体偶联合成/释放保留在铺覆的内皮细胞中。
