Neonatal sevoflurane anesthesia induces long-term memory impairment and decreases hippocampal PSD-95 expression without neuronal loss

摘要

AIM: Volatile anesthetics are widely used in the clinic, and sevoflurane is the most prevalent volatile anesthetic in pediatric anesthesia. Recent findings question the potential risks of volatile anesthetics on brain development. Evidence suggests that sevoflurane may cause neuronal deficiency. This study investigates the long-term effect of sevoflurane in the developing brain. MATERIALS AND METHODS: We anesthetized 7 day-old rats for 4 h with 2.5% sevoflurane. A Morris water maze was used to evaluate hippocampal function 7 weeks after sevoflurane exposure. Nissl staining was performed to analyze neuronal loss. PSD-95 (postsynaptic density protein-95) expression in the hippocampus was measured using a western blot. RESULTS: The exposure to 2.5% sevoflurane caused long-term deficits in hippocampal function and decreased hippocampal PSD-95 expression without neuronal loss. This study demonstrates that P7 rats exposed for 4 h to 2.5% sevoflurane have significant spatial learning and memory impairment 7 weeks after anesthesia. In addition, PSD-95 expression in the hippocampus decreased at P56 without neuronal loss. CONCLUSIONS: These data suggest that sevoflurane causes neurotoxicity in the developing brain, which may be attributed to decreased PSD-95 in the hippocampus.