Figure 8
TH-IR axons in the LA of a representative mouse. The LA was separated from the RA of the same representative mouse in Fig. 4. A montage of ~ 700 maximal projections in the LA showed that large TH-IR bundles entered the atrium at the LA-PV junction, traveled through cardiac ganglia, branched out to smaller axon bundles and extended individual axons that innervated the whole atrium with dense terminal varicosities. (Please zoom in 400 × to view details as well as see the following figures). ICG (asterisks), fat (arrow), white dotted line (boundaries of cut to separate the sinner auricle), yellow dotted line (opening of atrium), LA-PV left atrium-pulmonary vein junction, PV pulmonary vein. Scale bar: 500 μm.
