Ginkgo biloba exerts many pharmacological actions. It possesses antioxidant properties,the ability of neurotransmitter/receptor modulationand antiplatelet activation factor.This research is designed to investigate the neuroprotective effects of long-term treatment withEGb761 (a standard form of the extract of Ginkgo biloba leaf)in combination with MgSO(4),FK506, or MK-801 on the infarct volume of male gerbils’ brain induced by unilateral middle cerebral artery occlusion (MCAO).Thirty-five gerbils fed a standard diet were intragastrically given water or EGb761 (100 mg/kg/day) for one weekFive randomized groups were established: control (n = 7), EGb761 (n = 8), EGb761 + MgSO(4) (n = 7), EGb761 + FK506 (n = 7), and EGb761 + MK-801 (n = 6).The three drug-combination groups were injected with MgSO(4) (90 mg/kg), FK506 (0.5 mg/kg), or MK-801 (1 mg/kg), respectively30 min before MCAO.Gerbils were anesthetized and craniectomized to expose the right middle cerebral artery (MCA).
The right MCA was constricted with an 8-0 suture to produce a permanent ligation for 24 hours
Postmortem infarct volumes were determined by quantitative image analysis of 2,3,5-triphenyltetrazolium chloride (TTC)-stained brain sections.
Results showed that the total infarct volumes of the four treated groups either EGb761 alone or in combination with drugs were lower than the control group
by 36.1% (EGb761 alone), 40.3% (EGb761 + MgSO(4)), 35.3% (EGb761 + FK506), and 56.4% (EGb761 + MK-801), respectively (p < 0.01).