Assessment of impact of spreading depolarization during acute phase of subarachnoid hemorrhage model in rats

2015 Fiscal Year Final Research Report

• Project/Area Number: 25462217
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Neurosurgery
• Research Institution: Okayama University
• Principal Investigator: HISHIKAWA Tomohito 岡山大学, 大学病院, 助教 (60509610)
• Co-Investigator(Kenkyū-buntansha): TOKUNAGA Koji 岡山大学, 医歯薬学総合研究科, 准教授 (40294467) ; KAMEDA Masahiro 岡山大学, 医歯薬学総合研究科, 助教 (50586427)
• Co-Investigator(Renkei-kenkyūsha): DATE Isao 岡山大学, 医歯薬学総合研究科, 教授 (70236785) ; TAKEDA Yoshimasa 岡山大学, 大学病院, 准教授 (30294466)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: くも膜下出血 / 拡延性抑制 / NADH

Outline of Final Research Achievements

Changes in DC potential were categorized into three groups. In type 1, ischemic depolarization was not observed during one-hour of observation period. In type 2, DC potential showed ischemic depolarization upon initiation of SAH and recovered to 80% from maximal DC deflection during one-hour of observation period (33.3 ± 15.8 min). In type 3, DC potential showed ischemic depolarization and did not recover during one-hour of observation period. Based on histological evaluation at the DC recording sites, all sites in the type 1 group showed intact histology. In the type 2 and type 3 groups, neuronal damage of varying severity was observed depending on the duration of ischemic depolarization. The duration of depolarization that causes 50% neuronal injury (P50) was estimated at 22.4 minutes. CSD was successfully visualized using NADH fluorescence. CSD was not associated with histological damage in current experimental setting.

Free Research Field

医歯薬学、外科系臨床医学、脳神経外科学