Figure 5.

HAS2 suppresses excitability of developing neural networks. (A) Workflow of multielectrode array experiments for detection of action potentials propagation in neural networks. (B) Representative images of successful viral transduction on MEA plates as indicated by viral expression of ZsGreen in dissociated spheroid transduced with adenovirus constructs for control LacZ (AdZsGrnLacZ) and HAS (AdZsGrnHAS2) expression. (C) Quantification of weighted mean firing rate of spontaneous action potentials in HAS2 and LacZ-expressing dissociated spheroids demonstrates that HAS2 suppresses excitability by significantly reducing the firing rate at 24 and 72 h post-transduction. Tetrodotoxin (TTX) was used to inhibit action potential propagation, demonstrating that the firing rate reflects action potentials. n = 6 wells of dissociated spheroids per treatment. Spheroids were derived from 3 separately grown and transduced spheroid sets. * p ≤ 0.05 (D) Representative raster plots of spontaneous action potential firing at 0 (baseline), 24, 48, and 72 h post-transduction for AdZsGrnLacZ and AdZsGrnHAS2.