EXTRACT OF GINKGO-BILOBA (EGB-761) IMPROVES BEHAVIORAL PERFORMANCE AND REDUCES HISTOPATHOLOGY AFTER CORTICAL CONTUSION IN THE RAT

Male rats received bilateral frontal cortex contusions and were inject ed with 100 mg/kg of EGb 761 or an equal volume of vehicle beginning 5 min after injury and then with 1 injection/day for 7 days. The rats w ere tested for spontaneous motor behavior on days 1, 5, 10, and 15 pos tinjury and then for 10 days of spatial navigation performance in the Morris Water Maze (MWM), beginning on the day 8 after the contusion. B rain tissue was removed for examination on the 18th day after injury. Contused rats given EGb 761 performed more like intact rats on measure s of spontaneous motor activity while vehicle-treated counterparts rem ained more active than either shams or ECb 761-treated animals by the conclusion of testing. Contusion-only rats were worse than shams on sp atial performance, while those given EGb 761 were less impaired. Histo logical analyses indicated that EGb 761 failed to prevent loss of tiss ue at the primary site of impact. However, the extract reduced retrogr ade degeneration of neurons, gliosis in the thalamus, and ex vacuo hyd rocephalus. EGb 761 treatment also decreased the loss of ChAT-positive neurons in the dorsomedial caudate-putamen and in the nucleus basalis magnocellularis (NBM). The results of this study indicate that EGb 76 1 could be a possible treatment for traumatic brain injury. (C) 1997 E lsevier Science Ireland Ltd.