Exercise training normalizes enhanced glutamate-mediated sympathetic activation from the PVN in heart failure

摘要

Exercise training (ExT) in HF patients increases survival, decreases complications, and decreases muscle sympathetic nerve activity (13). In a rapid pacing model of HF in rabbits, ExT decreases RSNA to that of normal rabbits (23). However, the mechanism by which ExT normalizes sympathetic outflow in HF is not known. In the present study, we hypothesized that one mechanism by which ExT restores sympathetic outflow to normal levels in HF is by normalizing the increased glutama-tergic mechanisms within the PVN. Specifically, we wanted to determine whether ExT attenuated the increased RSNA response to NMDA injected into the PVN and whether ExT normalized the elevated expression of the NR1 subunit of the NMDA receptor in HF rats.