Effect of pilocarpine and substance P on ganglionic transmission

The effect of pilocarpine and substance P on the amplitudes of the postganglionic compound action potentials (unconditioned response, UR and post-train conditioned response, PTR) were studied in the isolated rabbit superior cervical ganglion (SCG). Pilocarpine (50 microM) and substance P (1 microM) produced an increase in the amplitudes of both UR & PTR responses in the rabbit SCG. Facilitation and subliminal fringe values decreased. It was concluded that both pilocarpine and substance P increase the amplitudes of the transmitted postganglionic compound action potentials and they may facilitate ganglionic transmission in the rabbit SCG.