Figure 5. Pharmacogenetic suppression of PV cells in vivo.

(A) Schematic illustrating the expression of GCaMP5G and PSAM^L141F-GlyR (PSAM) in PV cells. The PSAM agonist PSEM³⁰⁸ (PSEM) is injected intraperitoneally to suppress PV cell activity. (B)Co -expression of PSAM and GCaMP5G in PV cells imaged in vivo. Left: GCaMP5G fluorescence. Middle: dTomNLS fluorescence indicating PSAM expression. Right: merged image showing the co-localization of GCaMP5G (green) and PSAM (red) in PV cells. (C) Odor-evoked responses of the same PV cell before and after PSEM injection. Odor responses are transiently blocked following PSEM injection at Time 0 min and gradually recover to baseline levels over ~40 min. (D) Activity maps of PV cell population responses show that odor-evoked responses are strongly reduced following PSEM injection. Before: average across three trials before PSEM injection. PSEM: average across three trials following PSEM injection (8–24 min postinjection). Recovery: average across three trials one hour after PSEM injection. Left panel shows all imaged cells in white. (E) Change index (CI, see Experimental Procedures) summary of PV cell population activity for each trial. PSEM injection rapidly suppresses odor responses of PV cells in PSAM-expressing mice (filled circles, n = 3 mice, 35 cells), while having no effect on responses from non-PSAM-expressing control mice (open circles, n = 3 mice, 31 cells). Error bars represent SEM. See also Figure S4.