Fig. 1

Isoflurane induced age-related cognitive impairment. Young (6–8 months old) and aged (14 monts old) healthy male C57BL/6 mice were exposed to 1.5% isoflurane for 2 h. Some aged mice received intraperitoneal injection of 8 mg/kg Ac-YVAD-cmk 30 min before the isoflurane exposure. YC = blank control of young mice; Y-ISO = young mice exposed to isoflurane; AC = blank control of aged mice; A-ISO = aged mice exposed to isoflurane; A-ISO-cmk = Ac-YVAD-cmk administered before aged mice exposed to isoflurane; A-ISO-PBS = solvent of Ac-YVAD-cmk (PBS+ less than 1% DMSO) administered before aged mice exposed to isoflurane. Morris water maze test was carried out 1 week after the isoflurane anesthesia. a, b, and c Escape latency to reach the platform. d Target quadrant traveling time. Normalization of the target quadrant traveling time of group YC and Y-ISO was by the mean of group YC, and group AC, A-ISO, A-ISO-cmk, and A-ISO-PBS by the mean of group AC. e Platform-crossing times. f Average swimming speed on the sixth day. All results are mean ± SD (n = 15). #P < 0.05 and ##P < 0.01 compared with the corresponding data of group AC. *P < 0.05 compared with the corresponding data of group A-ISO