Effect of Gastrodia elata on learning and memory abilities and synaptic transmission protein expression of hippocampus in model rats with Alzheimer's disease

Objective To explore the effect of gastrodia elata on learning and memory abilities and synaptic transmission protein(P38, Ca2+ -CaMK Ⅱα, CREB)expression of hippocampus in model rats with Alzheimer's disease(AD). Methods 24 adult Wistar rats were randomly divided into control group, test group and intervention group. A dose of Aβ1-40 was injected into the hippocampus of rats on test group and intervention group, the control rats were injected with normal saline. When the models were successful, the rats of control group and test groups were given with sodium carboxymethyl cellulose(50g/kg), the rats of intervention group were given with gastrodia elata powder(50g/kg), lasting 15 days, Morris water maze test was used for learning and memory abilities study.The expression of P38, Ca2+ -CaMK Ⅱα and CREB protein were detected by immunohistochemistry method. Results Behavioral tests showed the mean escape latencies and search time of test group were obviously increased than those of control group and intervention group, the percentage of search distance on test groups was less than that of control group and intervention group(P<0.01). Immunohistochemistry results showed P38, Ca2+ -CaMK Ⅱα and CREB positive cells and optical density in hippocampus CA1 on test group were less than those of control group and intervention group(all P<0.01) (P38: 58.92±10.82, 0.208±0.037; Ca2+ -CaMK Ⅱα: 72.38±14.67, 0.174±0.036; CREB: 53.86±5.31, 0.161±0.043 in test group; P38: 87.32±9.56, 0.371±0.046; Ca2+ -CaMK Ⅱα: 98.16±16.29, 0.283±0.051; CREB: 86.76±7.73, 0.356±0.052 in intervention group; P38: 102.54±16.73, 0.563±0.078; Ca2+ -CaMK Ⅱα: 123.46±17.65, 0.436±0.057; CREB: 125.43±9.16, 0.524±0.057 in control group). Conclusion Gastrodia elata can treat AD by increasing expression of P38, Ca2+ -CaMK Ⅱα and CREB. Key words: Alzheimer‘s disease; Gastrodia elata; P38; Ca2+ -CaMK Ⅱα; CREB