Fig. 9. p75 immunostaining was confirmed as specific through the use of a p75 receptor (−/−) mouse.

p75 labeling of ICNs and cardiac nerve fibers was present in a wild-type (WT) mouse (B) and absent in a knockout (KO) mouse (D). TH staining of the same sections showed no differences between the WT mouse (A) and the p75 KO (C). All panels show maximum projection images compiled from confocal scans spanning 8 µm. Scale bars indicate 100 µm in (A and B) and (C and D).