title: Endothelin-induced modulation of neuropeptide Y and norepinephrine release from the rat mesenteric bed.
abstract: The effect of three endothelin (ET) agonists [ET-1, ET-3, and sarafotoxin (STX6C)] on the nerve stimulation-induced release of norepinephrine (NE) and neuropeptide Y-immunoreactive compounds (NPY-ir) from the perfused mesenteric arterial bed of the rat as well as the effect on perfusion pressure were examined. ET-1, ET-3, and STX6C all produced a significant, concentration-dependent decrease in the evoked release of NPY-ir but had no effect on the release of NE. In contrast, all three ETs potentiated the nerve stimulation-induced increase in perfusion pressure. The inhibition of nerve stimulation-induced NPY-ir release by ET-1 was significantly blocked by the ET(A)/ET(B) antagonist PD-142893 and the ET(B) antagonist RES-701-1 but not by the ET(A) antagonist BQ-123. The potentiation of the nerve stimulation-induced increase in perfusion pressure by ET-1 was significantly blocked by PD-142893 and BQ-123 and attenuated by RES-701-1. Prior exposure of the preparation to indomethacin or meclofenamate failed to alter the attenuation of the evoked release of NPY-ir or the potentiation of the increase in perfusion pressure produced by ET-1 or ET-3. These results are consistent with the idea that sympathetic cotransmitters can be preferentially modulated by paracrine mediators at the vascular neuroeffector junction.
authors.affiliation: Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, Missouri 63104, USA.
authors.forename: Dan
authors.initials: D
authors.lastname: Hoang
authors.forename: Heather
authors.initials: H
authors.lastname: Macarthur
authors.forename: Alice
authors.initials: A
authors.lastname: Gardner
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Westfall
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology; D004558:Electric Stimulation; D065128:Endothelin Receptor Antagonists; D019332:Endothelin-1 / Q000494:pharmacology*; D019334:Endothelin-3 / Q000494:pharmacology*; D008297:Male; D008638:Mesenteric Arteries / Q000294:innervation* / Q000378:metabolism; D009478:Neuropeptide Y / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism*; D009842:Oligopeptides / Q000494:pharmacology; D010456:Peptides, Cyclic / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000378:metabolism; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014757:Viper Venoms / Q000494:pharmacology
chemical_list: D000959:Antihypertensive Agents; D065128:Endothelin Receptor Antagonists; D019332:Endothelin-1; D019334:Endothelin-3; D009478:Neuropeptide Y; D009842:Oligopeptides; D010456:Peptides, Cyclic; D014662:Vasoconstrictor Agents; D014757:Viper Venoms; C057354:sarafotoxins s6; C076213:PD 142893; C087120:RES 701-1; C072247:cyclo(Trp-Asp-Pro-Val-Leu); D009638:Norepinephrine