Scavenging of reactive oxygen species mimics the anoxic response in goldfish pyramidal neurons

ABSTRACT Goldfish are one of a few species able to avoid cellular damage during month-long periods in severely hypoxic environments. By suppressing action potentials excitatory glutamatergic neurons, the goldfish brain decreases its overall energy expenditure. Coincident with reductions O2 availability is natural decrease reactive oxygen (ROS) generation, which has been proposed function as part low-oxygen signal transduction pathway. Using live-tissue fluorescence microscopy, we found that ROS production decreased by 10% onset anoxia telencephalic slices. Employing whole-cell patch-clamp recording, that, similar severe hypoxia, scavengers N-acetyl cysteine (NAC) and MitoTEMPO, added normoxic periods, depolarized membrane potential (severe hypoxia ?73.6 ?61.4 mV, NAC ?76.6 ?66.2 mV MitoTEMPO ?71.5 ?62.5 mV) increased conductance 5.7 nS 8.0 nS, 6.0 7.5 7.6 nS). Also, subset active pyramidal these treatments reduced firing frequency 0.18 Hz 0.03 Hz, 0.27 0.06 0.35 0.08 Hz). Neither nor scavenging impacted threshold. The addition exogenous hydrogen peroxide could reverse effects antioxidants. Taken together, this supports role for reduction [ROS] brain.