Figure 6
TH-IR axons in the RA of a representative mouse. The RA was separated from the LA and scanned using a 40 × oil objective lens. A montage of ~ 700 maximal projections in the RA showed large TH-IR bundles entered the atrium through the SVC and LPCV, traveled through the cardiac ganglia (asterisks), branched out to small axon bundles, and finally innervated the whole atrium with dense terminal varicosities. Intrinsic cardiac ganglia (asterisks), fat (arrow), white dotted line (boundaries of cut to separate the inner auricle), yellow dotted line (opening of the atrium) (Please zoom in 400 × to view details as well as see the following figures). RA right atrium, LPCV left precaval vein, SVC superior vena cava, IVC inferior vena cava, SAN sinoatrial node region, AVN atrioventricular node region. Scale bar: 500 μm.
