Bayar M Akif, Erdem Yavuz, Oztürk Koray, Beşcalti Omer, Caydere Muzaffer, Yücel Doğan, Buharali Zeki, Ustün Hüseyin
Department of Neurosurgery, Ankara Hospital, Ankara.
J Cardiovasc Pharmacol. 2003 Sep;42(3):395-402. doi: 10.1097/00005344-200309000-00011.
This study investigated the effects of Ginkgo biloba extract (EGb-76l), an anti-oxidant and platelet-activating factor antagonist, on basilar artery vasospasm in an experimental canine subarachnoid hemorrhage model. Morphometric analyses were performed, and serum and cerebrospinal fluid endothelin-l levels were measured by radioimmunoassay. Comparisons were made between treated and untreated groups. Twenty-four mongrel dogs were randomly assigned to three groups. The animals in group 1 (n = 8) were not subjected to subarachnoid hemorrhage and received no treatment. In this group, serum and cerebrospinal fluid endothelin-l levels were measured daily for 8 days. On day 9, the animals were killed and their basilar arteries were excised for histopathological examination. In group 2 (n = 8), subarachnoid hemorrhage was produced using autologous arterial blood, and daily intravenous boluses of saline were administered for the next 8 days. Assessments of endothelin-l levels and the basilar arteries were performed as described for group 1. In group 3 (n = 8), subarachnoid hemorrhage was produced using autologous arterial blood, and daily intravenous boluses of EGb-761 were administered for 8 days. Endothelin-1 levels and the basilar arteries were assessed as described above. The groups' serum endothelin-1, cerebrospinal fluid endothelin-1, and histopathological findings were compared. In group 1, the serum and cerebrospinal fluid endothelin-1 levels did not change significantly over the 8 days, and histopathological examination of the basilar arteries revealed no abnormalities. In group 2, the serum and cerebrospinal fluid endothelin-1 levels increased abruptly and significantly on day 2, and remained high to the end of the study period (day 8). Histopathological examination revealed marked vasospasm. In group 3, the serum and cerebrospinal fluid endothelin-1 levels followed the same pattern observed in group 2; however, the arteries showed significantly less vasospasm than that observed in group 2. The study findings did not provide information about the mechanism of action of the platelet-activating factor-antagonist EGb-761, but they clearly show that this agent decreases morphologic vasospasm in the dog basilar artery.
本研究在实验性犬蛛网膜下腔出血模型中，调查了抗氧化剂及血小板激活因子拮抗剂银杏叶提取物（EGb - 761）对基底动脉血管痉挛的影响。进行了形态计量分析，并通过放射免疫分析法测定血清和脑脊液中内皮素 - 1的水平。对治疗组和未治疗组进行了比较。24只杂种犬被随机分为三组。第1组（n = 8）的动物未发生蛛网膜下腔出血且未接受治疗。在该组中，连续8天每天测量血清和脑脊液中内皮素 - 1的水平。在第9天，处死动物并切除其基底动脉进行组织病理学检查。第2组（n = 8）使用自体动脉血制造蛛网膜下腔出血，随后8天每天静脉推注生理盐水。按照第1组的描述进行内皮素 - 1水平评估和基底动脉检查。第3组（n = 8）使用自体动脉血制造蛛网膜下腔出血，随后8天每天静脉推注EGb - 761。按照上述方法评估内皮素 - 1水平和基底动脉。比较了各组的血清内皮素 - 1、脑脊液内皮素 - 1及组织病理学结果。在第1组中，血清和脑脊液中内皮素 - 1水平在8天内未显著变化，基底动脉的组织病理学检查未发现异常。在第2组中，血清和脑脊液中内皮素 - 1水平在第2天突然显著升高，并在研究期结束时（第8天）保持在高位。组织病理学检查显示明显的血管痉挛。在第3组中，血清和脑脊液中内皮素 - 1水平呈现与第2组相同的模式；然而，动脉显示出的血管痉挛明显少于第2组。研究结果未提供关于血小板激活因子拮抗剂EGb - 761作用机制的信息，但清楚地表明该药物可减轻犬基底动脉的形态学血管痉挛。
