Figure 2.

mGluR/IICR-Signaling Cascade Promotes Clustering of GABA_AR and Gephyrin

(A–D) Effect of pharmacological blockade of IICR on GABA_AR (A and B) and gephyrin (C and D) clustering in 21–27 DIV hippocampal neurons. (A and C) Representative examples show GABA_AR (A) or gephyrin (C) immunoreactivity after 100 μM 2APB or 0.1% DMSO treatment for 30, 60, and 90 min. (B and D) The number of cluster per dendrite length (left) and fluorescence intensities (right) of synaptic GABA_AR (B) or gephyrin (D) clusters in cells exposed to DMSO (gray), 2APB (red), U73122 (blue), or MCPG (green) are shown. Plots show mean values ± SEM in function of time. Data were normalized to their respective control values.

(E) Time course of DHPG-induced intracellular Ca²⁺ elevation as reported by measurement of Fluo-4 F/F₀ ratio (means ± SEM; n = 41).

(F and G) Representative images (F) and quantifications (G) of the fluorescence intensity of synaptic GABA_AR clusters showing that DHPG increases GABA_AR clustering. Values (mean ± SEM) were normalized to their respective control values (n ≥ 30 cells per condition; ^∗∗∗p < 0.005, ^∗p < 0.05, t-test). Scale bars, 10 μm.

See also Figures S1–S5.