•NE inhibits bulbospinal RVL neurons by
activating alpha2-adrenoceptors (a2-ARs) located postsynaptically and presynaptically on glutamatergic
terminals.
•Contrary to our expectations, a2-ARs were also found on GABAergic inputs to these cells.
•
• Unlike the postsynaptic effects, the decrease of synaptic transmission by NE was not sensitive to
barium, indicating that different
mechanisms of action are involved in the pre- and postsynaptic effects of NE.
•
• Finally, all effects of NE were mimicked by the prototypical imidazoline ligand moxonidine which was
found to behave like an
a2-AR
agonist.