title: Effect of organ culture on noradrenaline- evoked contraction, calcium signalling and TRPC expression in rat mesenteric artery.
abstract: The aim of this study was to explore the changes evoked by organ culture in the signalling pathways activated by noradrenaline in rat resistance mesenteric artery. Contractile responses and calcium signalling were significantly more sensitive to noradrenaline in arteries cultured for 48-72 h in the absence of growth factors compared to fresh arteries. Both calcium release activated by noradrenaline in calcium-free solution and calcium entry measured after the addition of external calcium were higher in cultured arteries than in fresh tissue. Blockers of non-selective cation channels (SKF-96365, flufenamic acid, Gd(3+)) more potently inhibited noradrenaline contraction in cultured arteries than in fresh ones. The src kinase inhibitors genistein or PP2 normalised the increased contraction and the increased calcium release evoked by noradrenaline in cultured arteries. In cultured arteries, trpc1 (transient receptor potential canonical 1) mRNA expression was decreased by 47 +/- 8% (n = 5, p < 0.05), while trpc6 mRNA expression was increased by 92 +/- 24% (n = 5, p < 0.05) in comparison with non-cultured arteries. Immunofluorescence analysis of protein expression confirmed the up-regulation of TRPC6 protein after culture. These results indicate that mesenteric artery culture results in src kinase-dependent increase in the responses to noradrenaline and in a change in cation channel activity, which could contribute to the increased contraction.
authors.affiliation: Laboratories of Cellular Physiology, Université catholique de Louvain, Brussels, Belgium.
authors.forename: Khalid
authors.initials: K
authors.lastname: Tai
authors.forename: Greet
authors.initials: G
authors.lastname: Vandenberg
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Hamaide
authors.forename: Maurice
authors.initials: M
authors.lastname: Wibo
authors.forename: Nicole
authors.initials: N
authors.lastname: Morel
mesh_terms: D017607:Aluminum Compounds / Q000494:pharmacology; D000818:Animals; D020013:Calcium Signaling / Q000187:drug effects; D005459:Fluorides / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000819:agonists / Q000378:metabolism; D049990:Membrane Transport Modulators / Q000494:pharmacology; D008638:Mesenteric Arteries / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism*; D009924:Organ Culture Techniques; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D050052:TRPC Cation Channels / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors; D014661:Vasoconstriction / Q000187:drug effects; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D017607:Aluminum Compounds; D049990:Membrane Transport Modulators; D047428:Protein Kinase Inhibitors; D012333:RNA, Messenger; D050052:TRPC Cation Channels; C492145:Trpc6 protein, rat; C096351:transient receptor potential cation channel, subfamily C, member 1; C050992:tetrafluoroaluminate; D019061:src-Family Kinases; D019204:GTP-Binding Proteins; D005459:Fluorides; D009638:Norepinephrine