Supplementary Figure 2: Activation of Excitotoxic Panx1 currents requires both ligand binding sites of NMDARs.
From: Metabotropic NMDA receptor signaling couples Src family kinases to pannexin-1 during excitotoxicity
a) Representative whole-cell recordings from neurons in acute brain slices pre-blocked with either CGP-78608 (1μM) or APV (50μM) in 0Mg2+ aCSF. After a 15-minute baseline, the ligand for the unblocked site (100μM NMDA with CGP and 10μM glycine with APV) was applied to test sufficiency for Panx1 activation. Block of either ligand-binding site was sufficient to prevent Panx1 opening. b) Quantitative summary of charge transfer over time between treatment groups. c) Representative 2-photon images of dendrites from patched cells in “a&b”. Dendritic blebbing was not observed when either the glutamate or glycine ligand binding sites were blocked. d&e) Quantifications of changes in dendrite size (swelling) and the formation of dendritic blebs. f) Raw trace for a CGP washout experiment in the presence of NMDA. As an important control, pre-treatment of CGP prior to NMDA stim did not induce internalization of NMDA receptors and excitotoxic currents were present upon CGP washout. g) Average charge accumulation over time after CGP washout. h) Representative images illustrating the dendritic swelling/blebbing following CGP washout. i&j) Quantification of dendritic swelling/blebbing after CGP washout. All data are presented as mean±sem, * = p<0.05.
