title: Changes in reactivity of rat arteries subjected to dynamic stretch.
abstract: The effect of dynamic stretch on the reactivity of the rat tail and mesenteric artery segments was studied. Segments mounted on a myograph were stretched by a computer-controlled motorized micromanipulator. Dynamic stretch (1, 5 or 7 Hz) inhibited the artery constriction induced by noradrenaline (10 microM), 5-hydroxytryptamine (0.7 microM), or electrical field stimulation of intramural nerves. In contrast, dynamic stretch enhanced the tetrodotoxin-insensitive dilation induced by electrical field stimulation of noradrenaline-contracted arteries. Maximal increase of dilation evoked by electrical field stimulation (24.5 +/- 5.0% in mesenteric and 50.3 +/- 15.6% in the tail artery) was observed at a dynamic stretch-frequency of 5 Hz. An inhibitor of nitric oxide synthesis, NG-nitro-L-arginine (100 microM), abolished the difference in reactivity between static and dynamic conditions. The results indicate that dynamic stretch of the arteries activates nitric oxide synthesis/secretion, thus reducing constrictor and increasing dilator responses to the stimuli used.
authors.affiliation: Laboratory of Circulation, Pavlov Institute of Physiology, St Petersburg, Russia.
authors.forename: D P
authors.initials: DP
authors.lastname: Dvoretsky
authors.forename: V N
authors.initials: VN
authors.lastname: Yartsev
authors.forename: O V
authors.initials: OV
authors.lastname: Karachentseva
authors.forename: M P
authors.initials: MP
authors.lastname: Granstrem
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D004558:Electric Stimulation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000494:pharmacology; D008297:Male; D008638:Mesenteric Arteries / Q000502:physiology*; D019335:Nitroarginine / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000494:pharmacology; D013268:Stimulation, Chemical; D013314:Stress, Mechanical; D013623:Tail / Q000098:blood supply; D013779:Tetrodotoxin / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology*; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D016166:Free Radical Scavengers; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D019335:Nitroarginine; D012701:Serotonin; D013779:Tetrodotoxin; D000109:Acetylcholine; D009638:Norepinephrine