A-E. The PFC was stained with CB1 receptor (A1-D1, green) or 5HT6 receptor (E1-H1, green), Bassoon (A2 and E2, red), GAD65 (B2 and F2, red), PSD-95 (C2 and G2, red), or SERT (D2 and H2, red) antibodies. Merge images are also depicted (A3-H3). CB1 receptors were mainly co-localized with the presynaptic marker Bassoon (white arrows, A3), mostly within GABAergic boutons (white arrows, B3) and to a lesser extend with PSD-95 (white arrows, C3) and SERT (D3), while 5-HT6 receptors were mainly co-localized with PSD-95 (white arrows, G3). No co-localization of CB1 and 5-HT6 receptors was detected (white arrows indicate the 5-HT6 staining, H3). Scale bar: 10 μm. The scatter plot represents the co-localization analysis for CB1 and 5-HT6 receptor immunostainings. Graph on the top, Mander's split coefficient was used to identify the fraction of CB1 receptors that co-localizes with Bassoon (Mander's coefficient: 0.66 ± 0.02, n=4), GAD65 (Mander's coefficient: 0.56 ± 0.01, n=4), PSD95 (Mander's coefficient: 0.15 ± 0.01, n=4) or SERT (Mander's coefficient: 0.082 ± 0.004, n=4). Graph on the bottom. Mander's split coefficient was used to identify the fraction of 5-HT6 receptors that co-localizes with Bassoon (Mander's coefficient: 0.09 ± 0.01, n=4), GAD65 (Mander's coefficient: 0.059 ± 0.004, n=4), PSD95 (Mander's coefficient: 0.58 ± 0.01, n=4) or CB1 receptors (Mander's coefficient: 0.0020 ± 0.0004, n=4). Error bars correspond to the mean ± SEM. 