@RPSeal Contra side and also no stimulus control had very little signal. Maybe a single random GFP+ cell. Also, I should add that this is the native GFP fluorescence. I'm sure it would look much better with anti-GFP antibody, but that would be unrealistic for using it live. This is the Santa Cruz goat anti-Fos sc-52 (the original one, before they stopped selling it). This is also 14 um mounted slice, not free floating. Overall I'm satisfied with this.