Effect of esketamine on long-term cognitive dysfunction induced by propofol anesthesia in developing rats and the role of PI3K/Akt signaling pathway / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the effect of esketamine on long-term cognitive dysfunction induced by propofol anesthesia in the developing rats and the role of phosphatidylinositol-3-kinase (PI3K)/serine-threonine protein kinase (Akt) signaling pathway.Methods:Forty-eight clean-grade healthy Sprague-Dawley rats of either sex, aged 7 days, weighing 10-15 g, were divided into 4 groups ( n=12 each) using a random number table method: fat emulsion group (C group), propofol group (P group), esketamine + propofol group (EP group), and PI3K inhibitor LY294002 + esketamine + propofol group (LYEP group). Medium/long-chain fat emulsion injection 100 mg/kg was intraperitoneally injected in C group. Propofol was intraperitoneally injected at a dose of 50 mg/kg, followed by an additional dose of 50 mg/kg after the righting reflex was restored (40-60 min later) in P group. In group EP, esketamine 10 mg/kg was intraperitoneally injected, followed by propofol administration using the same method as previously described in P group. In LYEP group, LY294002 25 μg was injected via the lateral ventricle, 30 min later ketamine 10 mg/kg was intraperitoneally injected, and then propofol was given using the same method as previously described in P group. Six rats in each group were randomly sacrificed at 2 h after emergence for microscopic examination of pathological changes of hippocampal neurons and for determination of Akt, phosphorylated Akt (p-Akt), Bax, and cleaved caspase-3 in the hippocampal tissues (using Western blot). The remaining 6 rats in each group were subjected to Y-maze test to evaluate their learning and memory abilities at 30 days after birth. The p-Akt/Akt ratio was calculated. Results:Compared with C group, the p-Akt/Akt ratio in the hippocampal tissues was significantly decreased, the expression of Bax and cleaved caspase-3 was up-regulated, the number of training sessions required for learning was increased, the correct response rate was decreased ( P<0.05), and the pathological damage to neurons in hippocampal CA1 region was found in P, EP and LYEP groups. Compared with P group, the p-Akt/Akt ratio in the hippocampal tissues was significantly increased, the expression of Bax and cleaved caspase-3 was down-regulated, the number of training sessions required for learning was decreased, the correct response rate was increased ( P<0.05), and the pathological damage to neurons in hippocampal CA1 region was significantly attenuated in EP and LYEP groups. Compared with EP group, the p-Akt/Akt ratio in the hippocampal tissue was significantly decreased, and the expression of Bax and cleaved caspase-3 was up-regulated, the number of training sessions required for learning was increased, the correct response rate was decreased ( P<0.05), and the pathological damage to neurons in hippocampal CA1 region was aggravated in LYEP group. Conclusions:Esketamine can alleviate long-term cognitive impairment caused by propofol anesthesia in the developing rats, and the mechanism may be related to activation of the PI3K/Akt signaling pathway and inhibition of apoptosis in neurons.