银杏内酯及银杏黄酮对脑淋巴阻滞后鼠脑实质微循环血流量变化的影响

目的探讨蛛网膜下腔出血（SAH）后脑淋巴引流阻滞对脑缺血的影响和银杏内酯、银杏黄酮的保护作用。方法将雄性Wistar大鼠64只分为对照组、SAH组、SAH＋脑淋巴引流阻滞（CLB）组、SAH＋CLB＋溶剂组、SAH＋CLB＋银杏内酯组（又分20mg、80mg/kg组）、SAH＋CLB＋银杏黄酮组（又分50mg、200mg/kg组）。于第二次SAH后3d,用激光多普勒血流计针式探头记录脑实质局部血流量（rCBF）;放免法测定血浆内皮素-1（ET-1）含量。结果第二次SAH后3d,可见脑实质血流量明显降低,尤以SAH＋CLB组、SAH＋CLB＋溶剂组降低较为显著。SAH后血浆ET-1含量增加,SAH＋CLB组、SAH＋CLB＋溶剂组ET-1含量增加更为明显。银杏内酯、银杏黄酮可减轻CLB对SAH所致脑实质微循环血流量降低,降低血浆ET-1含量,且呈剂量依赖性。结论脑淋巴引流阻滞可显著加重SAH后脑实质血流量下降,银杏内酯和银杏黄酮对之具有一定改善作用。

Changes of Cerebral Blood Flow Following subarachnoid Hemorrhage After Blockade of Cerebral Lymphatic Drainage and the Influence of ginkgolide and ginkgetin

Objective To investigate the effects of blockade of cerebral lymphatic drainage on cerebral blood flow following subarachnoid hemorrhage and the protective effects of ginkgolide and ginkgetin. Methods The rats were divided into normal control, SAH group, SAH ＋ CLB group, SAH ＋ CLB ＋ Solvent group, higher and lower doses of ginkgolide （20mg, 80mg/kg） groups, higher and lower doses of ginkgetin （50mg, 200mg/kg） groups. On the third day after SAH, the regional cerebral essence blood flow （rCBF） was recorded with the laser Doppler. Plasam ET-1 was detected by radio immunoassay. Results The rCBF obviously reduced on the third day after SAH. Plasam ET-1 increased significiantly after SAH. The above pathological al- ternations were more severe in SAH ＋ CLB group and SAH ＋ CLB ＋ Solvent group than those in SAH group. Ginkgolide and ginkgetin partly attenuated above pathological alternations. Conclusion Cerebral lymphatic drainage pathway might play an important role in the pathophysiolagy of cerebral ischemic injury after SAH. Ginkgolide and ginkgetin may relieve the deterioration of the decreased cerebral blood flow by CLB after SAH.