Fig. 5

Calcineurin inhibition exhibited protection against the neurotoxicity of isoflurane. (A) Application of FK506 prevented STAT3 degradation induced by isoflurane in primary cortical neurons cultured for 5 days (n = 4, P < 0.001). The blots were cropped according to the ladders and then incubated with different antibodies. The contrast and brightness of the blot images were adjusted uniformly. (B) Representative images of double staining with TUNEL staining (green) and Doublecortin (red, a neuron marker) in neurons. Statistical analysis results of the percentage of TUNEL positive neurons normalized by the control group is shown in the right panel (4 wells per group, 6 images per well). FK506 pretreatment significantly reduced the number of apoptotic neurons after isoflurane exposure. Arrows indicated TUNEL-positive neurons. (C) The representative images of primary neurons stained with carboxy-H2DCFDA after isoflurane exposure are shown. FK506 attenuated the ROS accumulation after isoflurane exposure in primary neurons. Graph presenting quantification of the ROS level normalized by the control group is represented in the right panel (4 wells per group, 6 images per well). Scale bar, 20 μm. (D) Neurons were maintained in culture for 5 days after isoflurane exposure and then stained with drebrin (green). FK506 mitigated the impairment of neurite growth induced by isoflurane (4 wells per group, 6 images per well). Scale bar, 20 μm. ## P < 0.01 versus control, ** P < 0.01 versus isoflurane only