LAUSR

Exposure of neonatal rat to sevoflurane leads to neurodegeneration and deficits of spatial learning and memory in adulthood. However, the underlying mechanisms remain unclear. The type A γ‐aminobutyric acid receptor (GABAAR) is a target receptor for sevoflurane. The present study intends to investigate the changes in GABAAR α1/α2 expression and its relationship with the neurotoxicity effect due to sevoflurane in neonatal rats. After a dose–response curve was constructed to determine minimum alveolar concentration (MAC) and safety was guaranteed in our 7‐day‐old neonatal rat pup mode, we conducted two studies among the following groups: (A) the control group; (B) the sham anesthesia group; and (C) the sevoflurane anesthesia group and all three groups were treated in the same way as the model. First, poly(ADP‐ribose) polymerase‐1 protein (PARP‐1) expression was determined in the different brain areas at 6 hr after anesthesia. Second, the expression of PARP‐1 and GABAAR α1/GABAAR α2 in the hippocampus area was tested by Western blotting at 6 hr, 24 hr, and 72 hr after anesthesia in all three groups. After 4 hr, with 0.8 MAC (2.1%) sevoflurane anesthesia, the PARP‐1 expression was significantly higher in the hippocampus than the other brain areas (p < .05). Compared with Groups A and B, the expression of PARP‐1 in the hippocampus of Group C significantly increased at 6 hr after sevoflurane exposure (216% ± 15%, p < .05), and the ratio of the α1/α2 subunit of GABAAR surged at 6 hr (126% ± 6%), 24 hr (127% ± 8%), and 72 hr (183% ± 22%) after sevoflurane exposure in the hippocampus (p < .05). Our study showed that sevoflurane exposure of 0.8 MAC (2.1%)/4 hr was a suitable model for 7‐day‐old rats. And the exposure to sevoflurane could induce the apoptosis of neurons in the early stage, which may be related to the transmission from GABAAR α2 to GABAAR α1.