title: Sympathetic vasoconstriction takes an unexpected pannexin detour.
abstract: Sympathetic vasoconstriction plays an important role in the control of blood pressure and the distribution of blood flow. In this issue of Science Signaling, Billaud et al. show that sympathetic vasoconstriction occurs through a complex scheme involving the activation of large-pore pannexin 1 channels and the subsequent release of adenosine triphosphate that promotes contraction in an autocrine and paracrine manner. This elaborate mechanism may function as a point of intercept for other signaling pathways—for example, in relation to the phenomenon "functional sympatholysis," in which exercise abrogates sympathetic vasoconstriction in skeletal muscle. Because pannexin 1 channels are inhibited by nitric oxide, they may function as a switch to turn off adrenergic signaling in skeletal muscle during exercise.
authors.affiliation: The Danish National Research Foundation Centre for Cardiac Arrhythmia and Department of Biomedical Sciences, Faculty of Health Sciences, University of Copenhagen, Denmark. schak@sund.ku.dk.
authors.forename: Morten Schak
authors.initials: MS
authors.lastname: Nielsen
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000502:physiology*; D017630:Connexins / Q000378:metabolism*; D006801:Humans; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D018340:Receptors, Adrenergic, alpha-1 / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D014661:Vasoconstriction / Q000502:physiology*
chemical_list: D017630:Connexins; D009419:Nerve Tissue Proteins; D018340:Receptors, Adrenergic, alpha-1