OBJECTIVE: To investigate the effect of Ginkgo biloba leaf extract on amino acid levels in the cerebral cortex of cerebral ischemia model rats induced by middle cerebral artery occlusion (MCAO). METHODS: A rat model of cerebral ischemia was established by MCAO. Male rats were divided into a negative control group (Control), a sham-operated group (Sham), an ischemic group (MCAO), and an ischemic group treated with Ginkgo biloba leaf extract (MCAO_D). All groups were divided into two subgroups with occlusion times of 12 and 24 h, respectively. The levels of 18 endogenous amino acids in the cereb...