Cho J, Joo N E, Kong J Y, Jeong D Y, Lee K D, Kang B S
Department of Pharmacology, College of Medicine, Dongguk University, 780-714, Kyongju, South Korea.
J Ethnopharmacol. 2000 Nov;73(1-2):31-7. doi: 10.1016/s0378-8741(00)00262-2.
Acori graminei rhizoma (AGR) are reported to exhibit a number of pharmacological actions in the central nervous system. The effects of the methanol extract of AGR on excitotoxic neuronal death were evaluated in the present study using cultured rat cortical neurons. Based on the phase-contrast microscopic examinations of cultures and lactate dehydrogenase activities measured in the culture media, the glutamate-induced excitotoxicity was significantly inhibited by the extract. The inhibitory action of the extract was more potent and selective for the N-methyl-D-aspartate (NMDA) receptor-mediated toxicity. The AGR extract competed with [3H]MDL 105,519 for the specific binding to the glycine site of the NMDA receptor with the IC(50) value of 164.7 microg/ml. Modulation of the NMDA receptor activity by the extract was determined using [3H]MK-801 binding studies. The reduction of the binding in the presence of the extract indicated the receptor inactivation by AGR. These results demonstrated that the methanol extract of AGR exhibited protective action against excitotoxic neuronal death, and that the neuroprotective action was primarily due to the blockade of NMDA receptor function by the interaction with the glycine binding site of the receptor.
据报道，石菖蒲在中枢神经系统中具有多种药理作用。在本研究中，使用培养的大鼠皮质神经元评估了石菖蒲甲醇提取物对兴奋性毒性神经元死亡的影响。基于对培养物的相差显微镜检查和在培养基中测量的乳酸脱氢酶活性，提取物显著抑制了谷氨酸诱导的兴奋性毒性。提取物的抑制作用对N-甲基-D-天冬氨酸（NMDA）受体介导的毒性更有效且更具选择性。石菖蒲提取物与[3H]MDL 105,519竞争与NMDA受体甘氨酸位点的特异性结合，IC(50)值为164.7微克/毫升。使用[3H]MK-801结合研究确定提取物对NMDA受体活性的调节作用。提取物存在时结合的减少表明石菖蒲使受体失活。这些结果表明，石菖蒲甲醇提取物对兴奋性毒性神经元死亡具有保护作用，并且这种神经保护作用主要是由于与受体甘氨酸结合位点相互作用阻断了NMDA受体功能。
