Cahill P D, Brown B A, Handen C E, Kosek J C, Miller D C
Department of Cardiovascular Surgery, Stanford University School of Medicine, CA.
J Vasc Surg. 1987 Nov;6(5):496-503. doi: 10.1067/mva.1987.avs0060496.
Biochemical (or functional) adaptation of venoarterial grafts has been demonstrated recently. We reexamined one aspect of this biochemical "arterialization" process: prostacyclin (PGI2) production by canine venoarterial autologous grafts and the responsiveness of this biosynthetic pathway to maximal stimulation with substrate enhancement. Four reversed autologous grafts (femoral vein) were interposed into both carotid and femoral arteries in eight dogs. After 12 weeks, the grafts were removed, and radioimmunoassay was used to determine luminal surface production of 6-keto-PGF1 alpha (the stable metabolite of PGI2) in both the basal and stimulated (27 mumol/L arachidonic acid [AA]) states. PGI2 production by the venous autologous grafts was compared with that of control native artery and vein. We confirmed that PGI2 production (measured in nanograms per milliliter) by control artery was greater than vein under both basal conditions (5.8 +/- 0.4 [+/- SEM] vs. 2.7 +/- 0.5, p less than 0.001) and stimulated conditions (8.8 +/- 0.8 vs. 5.5 +/- 0.4, p = 0.002); moreover, AA stimulation significantly increased PGI2 production in both native artery and vein compared with basal PGI2 production. Under basal conditions, graft PGI2 production (6.3 +/- 1.6 ng/ml) was not significantly different than basal arterial levels (p = 0.8) but was higher than basal venous levels (p = 0.05). However, in marked contrast to both native artery and vein, the vein graft flow surface showed no significant response to substrate enhancement with AA: basal (6.3 +/- 1.6 ng/ml) vs. stimulated (5.9 +/- 0.9 ng/ml) (p = 0.8). These observations confirm that canine venoarterial autologous grafts undergo biochemical "arterialization"; however, this process appears to be an incomplete one.(ABSTRACT TRUNCATED AT 250 WORDS)
最近已证实静脉动脉移植物存在生化（或功能）适应性。我们重新审视了这种生化“动脉化”过程的一个方面：犬自体静脉动脉移植物中前列环素（PGI2）的产生以及该生物合成途径对底物增强最大刺激的反应性。在八只犬的颈动脉和股动脉中均植入四个自体反向移植物（股静脉）。12周后，取出移植物，采用放射免疫分析法测定在基础状态和刺激状态（27μmol/L花生四烯酸[AA]）下管腔表面6-酮-PGF1α（PGI2的稳定代谢产物）的产生量。将静脉自体移植物产生的PGI2与对照的天然动脉和静脉的PGI2产生量进行比较。我们证实，在基础状态（5.8±0.4[±SEM]对2.7±0.5，p＜0.001）和刺激状态（8.8±0.8对5.5±0.4，p = 0.002）下，对照动脉产生的PGI2（以每毫升纳克计）均高于静脉；此外，与基础PGI2产生量相比，AA刺激显著增加了天然动脉和静脉中的PGI2产生量。在基础状态下，移植物PGI2产生量（6.3±1.6 ng/ml）与基础动脉水平无显著差异（p = 0.8），但高于基础静脉水平（p = 0.05）。然而，与天然动脉和静脉形成鲜明对比的是，静脉移植物血流表面对AA底物增强无显著反应：基础状态（6.3±1.6 ng/ml）对刺激状态（5.9±0.9 ng/ml）（p = 0.8）。这些观察结果证实犬自体静脉动脉移植物会发生生化“动脉化”；然而，这一过程似乎并不完全。（摘要截短于250字）
