Figure 5. Perivascular convergence of neurotransmitters and neuropeptides in the periphery.
The vasculature is innervated by sensory, parasympathetic, and sympathetic autonomic nerves. Nerve fibers from sensory ganglia release CGRP, PACAP, nociceptin, and substance P-neurokinin A. Fibers from parasympathetic ganglia release PACAP, VIP, nitric oxide (NO) and the neurotransmitter acetylcholine (ACh). Fibers from sympathetic ganglia release neuropeptide Y (NPY), and the neurotransmitters noradrenaline (NA) and adenosine triphosphate (ATP).