STUDIES ON ATTENUATION OF POSTISCHEMIC BRAIN INJURY BY KAMPO MEDICINES-INHIBITORY EFFECTS OF FREE-RADICAL PRODUCTION .1.

In view of the recent investigation, highly reactive oxygen-derived free radicals may play a role in cerebral ischemia and brain damage, free radical scavenging activity of kampo formulations (Oren-gedoku-to, Keishi-bukuryogan, Saiko-ka-ryukotsu-borei-to and Daio-botampi-to) and Kampo components (Ityou, Shini, Menamomi, Arinosudama and Denshiti), used for the attenuation of brain damage, was investigated in vitro. The used experimental system was a radical scavenging action against 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide anion radical (O-2(radical-anion) ) and hydroxyl radical (OH.) by the electron spin resonance technique at room temperature. All kampo formulations and kampo components showed radical scavenging activity in a concentration-dependent manner. This result indicates that kampo formulations, treated for brain damage, were good radical scavenger that could possibly prevent ischemic complications such as formation of brain damage. The intensity of scavenging activity of kampo formulations for three types of radicals were as follows; 1. DPPH: Daiobotampi-to > Saiko-ka-ryukotsu-borei-to = Keishi-bukuryo-gan > Oren-gedokuto, 2. O-2(radical-anion): Daio-botampi-to = Keishi-bukuryo-gan > Saiko-ka-ryukotsu-borei-to > Oren-gedoku-to, 3. OH. : Daio-botampi-to=Saiko-ka-ryukotsu-borei-to > Keishi-bukuryo-gan=Oren-gedoku-to. Daio-botampi-to indicated the strongest scavenging activity against three types of radicals. Ischemic brain damage is thought to be an ''oketsu'' syndrome, which is correlated with abnormalities of the microcirculation. Therefore, Daio-botampi-to, which has been used for ''oketsu'' syndrome, showed superior free-radical scavenging activity.