Figure 4

Desflurane but not propofol decreased synaptic protein expression whereas ketamine increased synaptic protein expression, P110 attenuated anesthetic-induced detrimental changes to synaptic assembly. Representative fluorescent images of cortical neurons stained for PSD-95 and synaptophysin at day in vitro 10 (a–h). Each arrow on the merged images indicates examples of synaptic puncta along the neurite lengths as identified by the juxtaposed expression of pre-synaptic and post-synaptic labels that result in a distinctly yellow overlapping region. Quantification of average PSD-95/synaptophysin puncta per neurite length relative to control (i–j). Exposure to 4.3 Vol% desflurane decreased average synaptic puncta density. Treatment with 10 µM propofol did not affect average synaptic puncta density. Treatment with 5 µM ketamine increased average puncta density. P110 alone did not affect synaptic network assembly, whereas its pre-treatment mitigated desflurane-induced pertubations and partially prevented ketamine-induced synaptogenesis. P110 followed by propofol treatment did not differ from control. Two-Way ANOVA. * p < 0.05, ** p < 0.01, *** p < 0.001, as determined by pairwise comparison of post-hoc tests. Bars indicate ± SD measured across biological replicates. Each data point indicates the mean synapse density per biological replicate. Scale bars indicate 5 μm.