The Effects Of Ketamine Anaesthesia On The Learning And Memory Of Offspring Rats By EGF/NMDA/CREB/BDNF Pathway

Ketamine,as a anesthesia drug with excellent analgesic action,is widely used in veterinary clinic.Many studies have shown that ketamine during general anesthesia will cause damage to the nervous system,but these drugs affect fetal brain development are unclear.To investigate the effects of ketamine anesthesia during pregnancy on learning and memory function of offspring rats and the expression of NMDA,CERB and BDNF in hippocampus.To explore the mechanism of ketamine on learning and memory of offspring.It is of great significance to guide the rational formulation of drug doses,anesthesia programs,and prevention and control measures in the future.Thirty-six Wistar rats were divided into 12 groups.After mating in estrus,the vaginal plug was inspected and the sperm in the vagina of the female was recorded as 0 days pregnant.In 14days of pregnancy,ketamine was injected into female pregnant rats.The first day of birth of the offspring rat was recorded as B₀.In B₂₅-b₃₀,Morris water maze experiment,environmental fear experiment olfactory experiment were conducted to test the learning and memory ability of the offspring rats.The hippocampus was stained with Nissl to detect the density of neurons in the hippocampus,and Golgi staining was used to detect the dendritic synapse structure of hippocampal neurons.Western blot analysis detected the expression levels of EGFR,NR1,NR2B,CREB and BDNF in hippocampus.PC12 cells were cultured in vitro.The blank control group（C group）,DMSO control group（D group）,ketamine drug group（K group）,exogenous EGF group（E group）,EGFR inhibition group（Ei group）and ketamine were used.Exogenous EGF group（K+E group）.Western blot was used to detect the expression of EGFR,NR1,NR2B,CREB and BDNF in each group.Results:（1）Morris water maze test:The ketamine offspring rat had a slower learning rate than the control offspring rat,and the time taken to find the hidden platform was significantly longer than that of the control group（P<0.05）.In the exploratory experiment,the number of passages through the platform of the ketamine offspring rat was less than that of the control group,but the difference was not significant.（2）Olfactory test:There was no significant difference between the control group and the ketamine group.（3）Scenario fear experiment:The stagnation time of the two groups of offspring rat was higher than that of the training stage,and the difference was not significant.However,the control group’s ability to learn,memorize and integrate in the scene fear experiment was higher than that of the ketamine group.（4）Nissl’s staining experiment:Compared with the control group,the number of CA1 and CA3 neurons in the ketamine group was significantly decreased（P<0.05）.（5）Golgi staining:The density of basal dendrites in the ketamine group was 20.1%lower than that in the control group,and the apical basal density was 21.9%lower than that in the control group（P<0.05）.（6）The effect of ketamine on hippocampal protein expression:In addition to NR2A,the expression of other proteins in the ketamine group was lower than that of the control group.（7）The effect of ketamine on protein expression in PC12 cells:In addition to the ketamine group NR2A protein levels did not change significantly,the protein expression levels of EGFR,NR1,NR2B,CREB and BDNF were significantly lower than the control group（P<0.05）.The results showed that ketamine can down-regulate the protein expression levels of EGFR,NR1,NR2A,NR2B,CREB and BDNF,and can affect the learning and spatial memory ability of offspring by reducing the activity of NMDA receptor subunits.