title: Src tyrosine kinases contribute to serotonin-mediated contraction by regulating calcium-dependent pathways in rat skeletal muscle arteries.
abstract: The Src tyrosine kinase family contributes to the signalling mechanism mediating serotonin (5-hydroxytryptamine (5-HT))-induced vasoconstriction. These kinases were reported to influence the calcium sensitivity of the contractile apparatus. Whether Src kinases affect also the intracellular calcium concentration during constriction of intact arteries is unknown. Thus, we tested the hypothesis that constriction of arteries is associated with a Src kinase-dependent alteration of the intracellular calcium concentration. Contractility of gracilis arteries of Wistar rats was studied using isometric and isobaric myography. The intracellular calcium concentration was measured simultaneously with tension by FURA-2 fluorimetry. Inhibition of Src kinases with 10 μM PP2, 30 μM dasatinib and 100 μM AZM 475271 resulted in a strong attenuation of 5-HT-induced contractions. Vessel incubation with 10 μM PP3, an inactive analogue of PP2, had no effect. Removal of the endothelium did not alter vessel contractile responses to 5-HT nor the action of the Src-kinase inhibitor PP2. The PP2-mediated inhibition of 5-HT-induced contraction was associated with a reduced response of [Ca2+]ito 5-HT. In particular, inhibition of Src kinases attenuates 5-HT-induced calcium influx as well as calcium release from intracellular stores. In contrast, the calcium sensitivity of the contractile apparatus and the filling state of the sarcoplasmic reticulum were not influenced by Src kinases during 5-HT-induced contractions. We conclude that Src kinase activation is a powerful mechanism to produce vasoconstriction of small skeletal muscle arteries of rats. This effect is endothelium-independent. The data further suggest that the action of c-Src kinases is associated with a change in the intracellular calcium concentration that involves Ca2+entry and Ca2+release pathways.
authors.affiliation: Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, 68167, Mannheim, Germany.
authors.forename: Olga
authors.identifier: 0000-0001-6612-9753
authors.initials: O
authors.lastname: Zavaritskaya
authors.affiliation: Institute of Vegetative Physiology, University of Cologne, 50931, Cologne, Germany.
authors.forename: Lubomir T
authors.initials: LT
authors.lastname: Lubomirov
authors.affiliation: Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, 68167, Mannheim, Germany.
authors.forename: Serdar
authors.initials: S
authors.lastname: Altay
authors.affiliation: Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, 68167, Mannheim, Germany. rudolf.schubert@medma.uni-heidelberg.de.
authors.forename: Rudolf
authors.initials: R
authors.lastname: Schubert
mesh_terms: D000818:Animals; D001158:Arteries / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D020013:Calcium Signaling; D008297:Male; D018482:Muscle, Skeletal / Q000098:blood supply*; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000494:pharmacology*; D014661:Vasoconstriction; D019061:src-Family Kinases / Q000378:metabolism*
chemical_list: D012701:Serotonin; D019061:src-Family Kinases
keywords: 5﻿-HT/serotonin; Artery; Calcium; Smooth muscle; Tyrosine kinase; Vasoconstriction