Activation of trigeminal brain-stem nociceptive neurons by dural artery stimulation

Abstract

Vascular head pain is thought to result from activation of trigeminal sensory nerve fibers innervating cranial blood vessels. Support for this hypothesis was sought by searching in the trigeminal brain-stem subnucleus caudalis (SNC) for neuronal responses evoked by electrical stimulation of the middle meningeal artery (MMA). Seventy-eight SNC neurons were found which could be excited by MMA stimulation and of the 40 neurons studied in detail, 88% were also excited by noxious stimulation of the facial skin. These results provide the first report of the existence and functional properties of brain-stem neurons likely to be involved in mediating vascular head pain.