Jnj16259685

The mGluR1 antagonist JNJ16259685 (Tocris Bioscience) and the GABA_CR antagonist TPMPA (Tocris Bioscience) were added to the bath at 0.5 μM and 100 μM, respectively, using a calibrated syringe pump, as described previously [24 (link)]. Only one drug per retinal preparation was used to avoid possible long-term changes caused by the drug. The effects of a drug were examined only after the drug was bath applied for ~10 min to ensure stable responses.

Drugs were prepared as 1000× stocks and stored at −20°C. To induce homeostatic scaling, neurons were treated with 20 μm bicuculline methobromide (BCC; Tocris, 20 mm stock in water) or 1 μm tetrodotoxin citrate (TTX; Abcam, 1 mm stock in water) for 48 h (Fig. 1). In some live-cell imaging experiments, 20 μm BCC or 1 μm TTX was applied acutely for 10–60 min. For Figure 2, neurons were treated with 20 μm BCC for 4, 12, 24, or 48 h to monitor the process of homeostatic down-scaling. For Figure 3, neurons were treated for 48 h with a combination of 1 μm MTEP hydrochloride (Tocris, 1 mm stock in DMSO) and 100 nm JNJ 16259685 (Tocris, 100 μm stock in DMSO) to block mGluR1/5 signaling. For Figure 4, neurons were treated for 48 h with 100 nm PF3845 (Cayman, 100 μm stock in DMSO) or 2.5 μm PF3845 (Cayman, 2.5 mm stock in DMSO) to inhibit FAAH and to elevate AEA and related NAEs. For Figure 5, neurons were treated for 6 h with 50 nm AM251 (Cayman, 50 μm stock in DMSO), or for 10–60 min with 500 nm AM251 (Cayman, 500 μm stock in DMSO) to block CB1 signaling. For Extended Data Figure 5-1, neurons were treated for 10–60 min with 50 μm D-AP5 (Cayman, 50 mm stock in water) to block NMDA signaling.