Presence of nicotinic, purinergic and dopaminergic receptors and the TASK-1 K+-channel in the mouse carotid body

We have characterized the mouse carotid body (CB) with special attention to nicotinic, purinergic and dopaminergic receptors as well as the TASK-1 K+-channel. Mouse CB sections were stained immunohistochemically and visualized using fluorescent and confocal microscopy. The CB type 1 cells contained the α3 (n = 8), α4 (n = 7), α7 (n = 4) and β2 (n = 3) nicotinic acetylcholine receptor (nAChR) subunits, the ATP-receptors P2X2 (n = 15) and P2X3 (n = 9), the dopamine D2 receptor (n = 9) and the TASK-1 K+-channel (n = 7).Here we report the presence of α3, α4, α7 and β2 nAChR subunits, the D2 receptor and the TASK-1 K+-channel in the mouse CB. Also, we confirm the presence of the P2X2 and P2X3 receptors in mouse CB. Thus, we have localized nicotinergic, purinergic and dopaminergic receptors and the TASK-1 K+-channel on a protein level in one species. Our data are in line with the theory that the CB chemoreceptor cell hosts an orchestra of receptor systems that ultimately modulate the response to hypoxia.