Williams Bryn, Watanabe Coran M H, Schultz Peter G, Rimbach Gerald, Krucker Thomas
CVN-12, Department of Neuropharmacology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Neurobiol Aging. 2004 Aug;25(7):955-62. doi: 10.1016/j.neurobiolaging.2003.10.008.
EGb 761 is a standardized extract from the Ginkgo biloba leaf and is purported to improve age-related memory impairment. The acute and chronic effect of EGb 761 on synaptic transmission and plasticity in hippocampal slices from young adult (8-12 weeks) and aged (18-24 months) C57Bl/6 mice was tested because hippocampal plasticity is believed to be a key component of memory. Acutely applied EGb 761 significantly increased neuronal excitability in slices from aged mice by reducing the population spike threshold and increased the early phase of long-term potentiation, though there was no effect in slices from young adults. In chronically treated mice fed for 30 days with an EGb 761-supplemented diet, EGb 761 significantly increased the population spike threshold and long-term potentiation in slices from aged animals, but had no effect on slices from young adults. The rapid effects of EGb 761 on plasticity indicate a direct interaction with the glutamatergic system and raise interesting implications with respect to a mechanism explaining its effect on cognitive enhancement in human subjects experiencing dementia.
EGb 761是一种标准化的银杏叶提取物，据称可改善与年龄相关的记忆障碍。由于海马可塑性被认为是记忆的关键组成部分，因此测试了EGb 761对年轻成年（8 - 12周）和老年（18 - 24个月）C57Bl/6小鼠海马切片中突触传递和可塑性的急性和慢性影响。急性应用EGb 761可通过降低群体峰电位阈值显著增加老年小鼠切片中的神经元兴奋性，并增加长时程增强的早期阶段，而对年轻成年小鼠的切片没有影响。在以补充EGb 761的饮食喂养30天的慢性治疗小鼠中，EGb 761显著增加了老年动物切片中的群体峰电位阈值和长时程增强，但对年轻成年小鼠的切片没有影响。EGb 761对可塑性的快速影响表明其与谷氨酸能系统存在直接相互作用，并对解释其对患有痴呆症的人类受试者认知增强作用的机制提出了有趣的启示。
