Effect of sevoflurane combined with propofol anesthesia on postoperative expression of hnRNPA2 in brain tissues of rats with mild cognitive impairment

Abstract

Objective To evaluate the effect of sevoflurane combined with propofol anesthesia on the postoperative expression of nuclear heterogeneous ribonucleoprotein A2 (hnRNPA2) in brain tissues of rats with mild cognitive impairment (MCI). Methods Male Sprague-Dawley rats, aged 16-18 months, were anesthetized with pentobarbital sodium.MCI was induced by ligation of bilateral common carotid arteries after anesthesia.Forty-eight rats with MCI were divided into 4 groups (n=12 each) using a random number table method: sham operation group (SH group), sevoflurane anesthesia group (S group), propofol anesthesia group (P group), and sevoflurane combined with propofol anesthesia group (SP group). Group S inhaled 3% sevoflurane.Propofol was intravenously infused at a rate of 40 mg·kg-1·h-1 in group P. In group SP, 1.7% sevoflurane was inhaled, and propofol 20 mg·kg-1·h-1 was intravenously infused.The anesthesia time was 3 h in the three groups.After disappearance of eyelash reflex, open reduction and internal fixation was performed after tibial fracture was induced.Y-maze test was performed at 7 days after operation, and the percentage of time of staying at novel arm was calculated.The open field test was performed, and the total activity distance and time of staying at the central region were recorded.Then the rats were sacrificed, and brain tissues were obtained for determination of the expression of hnRNAP2 and γ-aminobutyric acid receptor A1 subunit (GABAA-α1) in hippocampus by immunofluorescence and Western blot, respectively. Results Compared with SH group, the percentage of time of staying at novel arm was significantly decreased, the expression of hnRNPA2 in the hippocampus was up-regulated, and the expression of GABAA-α1 was down-regulated in S and P groups, and the expression of hnRNPA2 in the hippocampus was up-regulated (P 0.05). Compared with S group or P group, the percentage of time of staying at novel arm was significantly increased, the expression of hnRNPA2 in the hippocampus was down-regulated, and the expression of GABAA-α1 was up-regulated in SP group (P 0.05). Conclusion The mechanism by which sevoflurane combined with propofol anesthesia does not aggravate the postoperative cognitive dysfunction may be related to up-regulating the expression of hnRNPA2 in brain tissues and maintaining GABAA-α1 stable in rats with MCI. Key words: Anesthetics, inhalation; Propofol; Cognition disorders; Heterogeneous nuclear ribonucleoprotein A2