NMDA recepter-mediated neuroprotection by essential oils from the rhizomes of Acorus gramineus.
Acori graminei Rhizoma (AGR) is shown to exhibit a number of pharmacological actions including sedation and anticonvulsive action. To further characterize its actions in the CNS, the present study evaluated the effects of essential oils (EO) from AGR on the excitotoxic neuronal cell death induced in primary rat cortical cell cultures. EO inhibited the glutamate-induced excitotoxicity in a concentration-dependent manner, with the IC50 of 0.241 mg/ml. EO exerted more potent neuroprotection against the toxicity induced by NMDA (IC50 = 0.139 mg/ml). In contrast, the AMPA-induced toxicity was not inhibited by EO. Receptor-ligand binding studies were performed to investigate the neuroprotective action mechanism. EO dramatically inhibited the specific bindings of a use-dependent NMDA receptorion channel blocker [3H]MK-801, indicating an NMDA receptor antagonist-like action. However, the bindings of [3H]MDL 105,519, a ligand selective for the glycine binding site of NMDA receptor, were not considerably inhibited. These results demonstrated that EO extracted from AGR exhibited neuroprotective effects on cultured cortical neurons through the blockade of NMDA receptor activity, and that the glycine binding site appeared not to be the major site of action.
Cho
J
J
Department of Pharmacology, College of Medicine, Dongguk University, Kyongju, Kyongbuk, Korea. jscho@mail.dongguk.ac.kr
Kong
J Y
JY
Jeong
D Y
DY
Lee
K D
KD
Lee
D U
DU
Kang
B S
BS
D000818:Animals; D016923:Cell Death / Q000187:drug effects; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000187:drug effects* / Q000196:embryology / Q000378:metabolism; D016291:Dizocilpine Maleate / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D007211:Indoles / Q000378:metabolism; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D016202:N-Methylaspartate / Q000633:toxicity*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D018696:Neuroprotective Agents / Q000494:pharmacology*; D009822:Oils, Volatile / Q000494:pharmacology; D010938:Plant Oils / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D013570:Synaptic Membranes / Q000187:drug effects / Q000378:metabolism
D007211:Indoles; C101788:MDL 105519; D018696:Neuroprotective Agents; D009822:Oils, Volatile; D010938:Plant Oils; D016194:Receptors, N-Methyl-D-Aspartate; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate