Blaise G A, Parent M, Laurin S, Omri A, Reader T A, Moutquin J M
Department of Anesthesia, University of Montreal, Quebec, Canada.
J Cardiothorac Vasc Anesth. 1994 Apr;8(2):175-81. doi: 10.1016/1053-0770(94)90058-2.
To determine the effect of 1.5 MAC of two volatile anesthetics (halothane and isoflurane) on platelet-induced contraction of canine coronary artery, isolated, denuded coronary rings were suspended between two stirrups, placed into organ chambers filled with an oxygenated Krebs-Ringer solution, and connected to an isometric force transducer. Human platelets were obtained from healthy donors and introduced into the organ chambers in increasing amounts to reach 20,50 and, 70 x 10(9) platelets/L. The tension generated in both the control and anesthetic-treated rings was recorded; only halothane reduced the tension induced by platelet activation in the organ chambers. In some experiments, aliquots of Krebs-Ringer solution were taken to determine the amount of 5-HT and TB2 released by 70 x 10(9) human platelets in the presence and absence of the anesthetics. Only halothane reduced TA2 production by the activated platelets. Finally, the contractile response of isolated denuded canine coronary artery rings to U46619, a thromboxane analog, was measured in the presence and absence of the anesthetics. Neither halothane nor isoflurane attenuated the response. In another series of experiments, in vitro platelet aggregation was induced by epinephrine, collagen, ADP, or arachidonic acid in the presence or absence of 1.5 MAC isoflurane or halothane. Both anesthetics significantly reduced the aggregation.
为了确定两种挥发性麻醉剂（氟烷和异氟烷）的1.5倍最低肺泡有效浓度（MAC）对血小板诱导的犬冠状动脉收缩的影响，将分离的、剥脱内皮的冠状动脉环悬挂在两个马镫之间，放入充满氧合的克雷布斯-林格溶液的器官浴槽中，并连接到一个等长力传感器上。从健康供体获取人血小板，并以递增的量引入器官浴槽中，使其达到20、50和70×10⁹个血小板/升。记录对照环和经麻醉处理的环中产生的张力；只有氟烷降低了器官浴槽中血小板激活诱导的张力。在一些实验中，取等分的克雷布斯-林格溶液以测定在有和没有麻醉剂的情况下70×10⁹个人血小板释放的5-羟色胺（5-HT）和血栓素B2（TB2）的量。只有氟烷减少了活化血小板产生的血栓素A2（TA2）。最后，在有和没有麻醉剂的情况下，测量分离的剥脱内皮的犬冠状动脉环对血栓素类似物U46619的收缩反应。氟烷和异氟烷均未减弱该反应。在另一系列实验中，在有或没有1.5倍MAC异氟烷或氟烷的情况下，用肾上腺素、胶原、二磷酸腺苷（ADP）或花生四烯酸诱导体外血小板聚集。两种麻醉剂均显著降低了聚集。
