Expressions of P2X2 and P2X3 receptors in rat nodose neurons after myocardial ischemia injury

The role of ATP is as a functional neurotransmitter and local intercellular signaling molecule. The nodose neurons express both P2X2 and P2X3 subunits in their plasma membrane. This study wants to observe the expression of P2X2 receptor and the expression relationship between P2X2 and P2X3 in nodose neurons after myocardial ischemic injury. The expressions of P2X3 immunoreactivity, mRNA and protein were analyzed by immunohistochemistry, in situ hybridization and western blotting. P2X2 and P2X3 immunoreactivity, mRNA expression had been increased after myocardial ischemia in nodose neurons. Myocardial ischemia enhanced P2X2 and P2X3 protein level in nodose ganglia after myocardial ischemia. P2X2 receptor in nodose neurons participated in the transmission of cardiac pain. The changes of P2X2 and P2X3 immunoreactivities, mRNA and protein that occurred following myocardial ischemic injury in the nodose ganglia showed that a correlation existed between P2X2 and P2X3 expression. It suggests that P2X2 receptor subtype in company with P2X3 receptor subtype plays the important role in cardiac vagal sensory nociceptors with a sensitivity to ATP.