Sphingosine-1-phosphate modulates spiral modiolar artery tone: A potential role in vascular-based inner ear pathologies?

Cardiovascular Research
Elias Q SchererSteffen-Sebastian Bolz

Abstract

The mechanisms regulating spiral modiolar artery (SMA) tone are not known, yet their characterization is pivotal for understanding inner ear blood flow regulation. Sphingosine-1-phosphate (S1P), known to stimulate vasoconstriction in several vascular beds, is a candidate regulator of SMA tone with potential pathophysiological relevance. Gerbil SMAs were isolated, cannulated and pressurized (30 mm Hg transmural) for experimentation under near-in vivo conditions. For functional experiments, vascular diameter and intracellular Ca2+ were simultaneously measured. Standard RT-PCR and immunohistochemical techniques were also employed. mRNA transcripts encoding sphingosine kinase, S1P phosphohydrolase and three S1P receptors (S1P(1-3)) were detected in the SMA. S1P induced dose-dependent vasoconstriction of the SMA (EC50 = 115 nmol/L), and enhanced the apparent Ca2+-sensitivity of the contractile apparatus. Noradrenaline did not elicit vasoconstriction. The Rho kinase inhibitor Y27632 (1 micromol/L) reversed S1P-induced vasoconstriction and the S1P-mediated enhancement of Ca2+-sensitivity. RhoA was observed to translocate to the plasma membrane in response to stimulation with 30 micromol/L S1P. We conclude that all key signalling pathw...Continue Reading

Citations

Jul 7, 2010·Lab on a Chip·Axel GüntherSteffen-Sebastian Bolz
Oct 12, 2010·Stroke; a Journal of Cerebral Circulation·Elias Q SchererSteffen-Sebastian Bolz
Mar 30, 2007·Acta Paediatrica. Supplement·Martin C MichelStephan L M Peters
Jun 22, 2013·International Journal of Audiology·Warangkana ArpornchayanonSebastian Strieth
Jun 19, 2016·The Journal of Pharmacology and Experimental Therapeutics·Anna Cantalupo, Annarita Di Lorenzo
Nov 5, 2016·Annual Review of Physiology·Keisuke Yanagida, Timothy Hla
Aug 19, 2007·Journal of Lipid Research·Kelley M Argraves, W Scott Argraves
Jun 4, 2011·Otolaryngology--head and Neck Surgery : Official Journal of American Academy of Otolaryngology-Head and Neck Surgery·Warangkana ArpornchayanonSebastian Strieth
Sep 30, 2006·Circulation Research·Ravichandran RamasamyAnn Marie Schmidt
Feb 8, 2007·The Journal of Biological Chemistry·Mari KonoRichard L Proia
Jun 14, 2016·Otology & Neurotology : Official Publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology·Kariem SharafMartin Canis
Aug 21, 2013·The Annals of Otology, Rhinology, and Laryngology·Friedrich IhlerMartin Canis

❮ Previous
Next ❯

Related Concepts

Related Feeds

Calcium & Bioenergetics

Bioenergetic processes, including cellular respiration and photosynthesis, concern the transformation of energy by cells. Here is the latest research on the role of calcium in bioenergetics.