[Effect of extracts of Ginkgo biloba leaf on learning-memory ability and NMDA receptor 1 expression in the hippocampus in rats with kindling-induced epilepsy].
OBJECTIVE
To study the effect of extracts of Ginkgo biloba leaf (EGb), a catalyzer of central nervous system, on learning-memory ability and possible mechanism in rats with kindling-induced epilepsy.


METHODS
Forty postnatal day 21 (P21) and 40 postnatal day 35 (P35) Sprague-Dawley (SD) rats were randomly respectively assigned to five groups: normal sodium (NS) control, kindling epilepsy model, high, middle and low dosage of EGb-treated kindling epilepsy. The kindling epilepsy model was established by an intraperitoneal injection of pentetrazole (PTZ). The learning-memory ability and NMDA receptor 1 (NMDAR1) expression in the hippocampus were measured by Y-maze test and immunohistochemistry assay respectively.


RESULTS
The stimulation times for reaching to academic standard in the Y-maze test in the two ages PTZ kindling groups was significantly more than that in the corresponding NS control groups (P<0.01). After EGb treatment the achievement of the Y-maze test in the three treatment groups was significantly improved in a dose-dependent manner, the higher the dosage, the better the achievement (P<0.01). Immunohistochemistry assay showed that the expression of NMDAR1 in the two ages PTZ kindling groups was significantly higher than that in the corresponding NS control groups (P<0.01). Compared with the corresponding untreated kindling model groups, the expression of NMDAR1 in the two ages EGb treatment groups was significantly reduced in a dose-dependent manner (P<0.01).


CONCLUSIONS
EGb can improve learning-memory ability in epileptic rats at different developmental phases in a dose-dependent manner, possibly through a reduction of NMDAR1 expression in the hippocampus.
Duan
Fang-Rong
FR
Department of Pediatrics, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, China.
Yuan
Bao-Qiang
BQ
D000818:Animals; D004827:Epilepsy / Q000188:drug therapy* / Q000523:psychology; D005260:Female; D020441:Ginkgo biloba; D006624:Hippocampus / Q000737:chemistry*; D007150:Immunohistochemistry; D007696:Kindling, Neurologic; D007858:Learning / Q000187:drug effects*; D008297:Male; D008568:Memory / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000032:analysis*
D010936:Plant Extracts; D016194:Receptors, N-Methyl-D-Aspartate