Effects of different duration of sevoflurane anesthesia in neonatal period on long-term cognitive func-tion and hippocampal synaptic plasticity in rats / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effects of different duration of sevoflurane anesthesia in the neonatal period on the long?term cognitive function and hippocampal synaptic plasticity in rats. Methods Twenty?four pathogen?free healthy Sprague?Dawley rats of both sexes, aged 7 days, weighing 12-16 g, were divided into 3 groups ( n=8 each) using a random number table control group ( group C) , sevoflu?rane anesthesia for 2 h group ( group S1 ) , and sevoflurane anesthesia for 6 h group ( group S2 ) . Group S1 and group S2 inhaled 2% sevoflurane for 2 and 6 h, respectively. Morris water maze test was performed at 30 days after the end of anesthesia ( postnatal day 37) to assess the cognitive function. After the end of the test, the rats were sacrificed, and hippocampi were isolated for determination of the expression of brain?de?rived neurotrophic factor ( BDNF) , postsynaptic density?95 ( PSD?95) and synapsin 1 in hippocampal tis?sues by Western blot. Results Compared with group C, the escape latency on 4th and 5th days of the test in group S1 and on 2nd-5th days of the test in group S2 was significantly prolonged, and the frequency of crossing the original platform was significantly decreased, and the time of staying at the platform quadrant was significantly shortened in S1 and S2 groups, the expression of BDNF, PSD?95 and synapsin 1 in hipp?ocampal tissues was significantly down?regulated in group S2 (P0?05) . Compared with group S1 , no significant change was found in the escape latency and frequency of crossing the original platform (P>0?05), the time of staying at the platform quadrant was significantly shortened, and the expression of BDNF, PSD?95 and synapsin 1 in hippocampal tissues was significantly down?regula?ted in group S2 ( P<0?05) . Conclusion Short?time and long?time sevoflurane anesthesia both can induce long?term cognitive dysfunction in the neonatal period, and the severity is aggravated with prolonged anes?thesia; the partial mechanism is related to inhibition of the synaptic plasticity of hippocampal neurons of rats.