Figure 1.

NRG1 facilitates excitatory synapse development in cortical GABAergic interneurons. NRG1 at 5 nm was applied to low-density DIV5, DIV12, and DIV19 dissociated cortical neurons for 2 d. GABA and PSD-95 were stained to represent GABAergic interneurons and excitatory synapses, respectively. A–C, The immunoreactivities of GABA and PSD-95 without or with NRG1 treatment at different developmental. A segment (30 μm) of primary or secondary dendrites was subjected for the analysis of PSD-95 puncta number and size. D, E, Average PSD-95 puncta number (D) and size (E). Data shown are the mean ± SEM of four individual experiments. *p < 0.05; **p < 0.01 (DIV5 + 2, n = 43 and 46 for control and treated group; DIV12 + 2, n = 46 and 54 for control and treated group; DIV19 + 2, n = 78 and 73 for control and treated group). For DIV5 + 2, DIV12 + 2, and DIV19 + 2 neurons, respectively, puncta numbers are 8.72 ± 1.73, 14.9 ± 1.05, and 19.7 ± 1.37 in the absence of NRG1 and 13.4 ± 1.69, 19.6 ± 1.54, and 20.7 ± 1.20 in the presence of NRG1; sizes are 10.6 ± 1.12, 17.93 ± 1.73, and 22.2 ± 1.12 in the absence of NRG1 and 19.2 ± 3.03, 24.31 ± 1.95, and 29.5 ± 1.65 in its presence. Scale bar: (in C) A–C, 30 μm; boxed area was enlarged in the respective bottom image.