蛛网膜下腔出血后发生的脑血管痉挛,其原因尚不明了,但由于其对患者的预后影响较大,故脑外科医师颇为重视。虽然不少报告提出此现象与花生四烯酸系统有关,但一般认为系多种因素所致。实验及临床研究发现,环氧化酶系中的PGD_2、PGE_2、PGF_(2α)和TXA_2对脑动脉有收缩作用,蛛网膜下腔出血时,其在脑脊液中的浓度可显著增加。然而,其动态变化与脑血管痉挛的发生并不相关,而且浓度也不像体外实验那样使血管收缩时那样强。佐佐木等用狗做蛛网膜下出血动物模型,研究了蛛网膜下腔出血时,脑血管产生PGI_2的能力。结果表明,尽管PGI_2的产生随时间延长而降低,但在组织学上 The causes of cerebral vasospasm occurring after subarachnoid hemorrhage are unknown, but brain surgeons place considerable emphasis on their prognosis. Although many reports suggest that this phenomenon is related to the arachidonic acid system, it is generally considered to be caused by a variety of factors. Experimental and clinical studies have found that PGD_2, PGE_2, PGF_ (2α) and TXA_2 in the cyclooxygenase system have a contractile effect on the cerebral arteries. In subarachnoid hemorrhage, the concentrations of PGD_2, PGE_2, TXB2 and TXB2 can be significantly increased in cerebrospinal fluid. However, its dynamic changes are not related to the occurrence of cerebral vasospasm, nor do they have the same concentration as in in vitro experiments. Sasaki and other dogs with subarachnoid hemorrhage animal model of subarachnoid hemorrhage, cerebrovascular production of PGI_2 ability. The results showed that, although PGI_2 production decreased with time, but histologically