Transmission in airway ganglia of ferrets: inhibition by norepinephrine.

We examined the possibility that norepinephrine inhibits transmission in parasympathetic ganglia of the ferret trachea. We impaled ganglion cells on recording microelectrodes and evoked postsynaptic action potentials by stimulating fiber tracts entering the ganglion. When norepinephrine was added to the recording bath, the action potentials were blocked. Phentolamine reversed this block. These results indicate that, by activating alpha-receptors, norepinephrine inhibits transmission in airway ganglia.