Physiology of meningeal innervation: aspects and consequences of chemosensitivity of meningeal nociceptors.
Up to now, the cause of most types of headaches is unknown. Why headache starts or why it fades away during hours or a few days is still a mystery. This phenomenon makes headache unique compared to other pain states. For long it has been known that during headache sensory structures in the meninges are activated. But it was not until the last two decades that scientists investigated the physiology of the sensory innervation of the meninges. Animal models and in vitro preparations have been developed to get access to the meninges and to determine the response properties of meningeal afferents. Although animals hardly can tell their pain, blood pressure measurements and observations of behaviour in two models of headache suggest that such animal models are valid and may add remarkable information to our understanding of human headache. Since chemicals and endogenous inflammatory mediators may alter sensory thresholds and responsiveness of neurons, they are putative key molecules in triggering pathophysiological sensory processing. This review briefly summarizes what is known about the chemosensitivity of meningeal innervation.
Ebersberger
A
A
Department of Physiology I, University of Jena, Germany. aebe@mti-n.uni-jena.de
D000344:Afferent Pathways / Q000187:drug effects; D000818:Animals; D001920:Bradykinin / Q000378:metabolism; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D004195:Disease Models, Animal; D006261:Headache / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D008578:Meninges / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology*; D015288:Neurokinin A / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism*; D009619:Nociceptors / Q000187:drug effects / Q000502:physiology*; D011453:Prostaglandins / Q000378:metabolism*; D013373:Substance P / Q000378:metabolism
D009479:Neuropeptides; D011453:Prostaglandins; D013373:Substance P; D015288:Neurokinin A; D015740:Calcitonin Gene-Related Peptide; D015232:Dinoprostone; D001920:Bradykinin