Rosenblum W I, El-Sabban F, Ellis E F
Am J Physiol. 1980 Aug;239(2):H220-6. doi: 10.1152/ajpheart.1980.239.2.H220.
The cyclooxygenase inhibitors aspirin and indomethacin enhanced platelet aggregation in mesenteric vessels, suggesting that the normal mesentery produces an antiaggregatory prostaglandin. Testing of mesentery incubate in mouse platelet-rich plasma disclosed an antiaggregatory material with the properties of prostacyclin. Chromatography showed that mesentery made several radiolabeled products from [3H]arachidonic acid, including one that cochromatographed with 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha), the stable hydrolysis product of prostacyclin. Gas chromatography-mass spectrometric analysis of mesentery incubate showed the presence of 6-keto-PGF1 alpha, synthesized from the mesentery's endogenous arachidonic acid. The enhancement of platelet aggregation in mesenteric vessels contrasts with earlier data showing that in similarly injured mouse cerebral vessels aggregation was retarded by both aspirin and indomethacin. This divergent effect of cyclooxygenase inhibitors in different vascular beds may depend on the relative importance of prostacyclin in the different beds or on the capacity of cyclooxygenase inhibitors to influence this prostacyclin production in different beds. Caution is urged before acceptance of a central role for PGI2, however, because of the capability of microvasculatures and adjacent tissue to synthesize a number of other products whose interaction with platelets and with aspirin and indomethacin remains to be elucidated.
环氧化酶抑制剂阿司匹林和吲哚美辛可增强肠系膜血管中的血小板聚集，这表明正常的肠系膜会产生一种抗聚集性前列腺素。在富含小鼠血小板的血浆中对肠系膜孵育物进行检测，发现了一种具有前列环素特性的抗聚集物质。色谱分析表明，肠系膜可从[3H]花生四烯酸生成几种放射性标记产物，其中一种与前列环素的稳定水解产物6-酮前列腺素F1α（6-keto-PGF1α）共色谱。对肠系膜孵育物进行气相色谱-质谱分析，结果显示存在由肠系膜内源性花生四烯酸合成的6-酮-PGF1α。肠系膜血管中血小板聚集的增强与早期数据形成对比，早期数据表明，在同样受损的小鼠脑血管中，阿司匹林和吲哚美辛均可抑制聚集。环氧化酶抑制剂在不同血管床中的这种不同作用可能取决于前列环素在不同血管床中的相对重要性，或者取决于环氧化酶抑制剂影响不同血管床中前列环素生成的能力。然而，由于微血管和相邻组织能够合成多种其他产物，它们与血小板以及阿司匹林和吲哚美辛之间的相互作用仍有待阐明，因此在接受PGI2的核心作用之前需谨慎。
