These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Pre- and postjunctional modulation by endothelin-1 of the adrenergic neurogenic response in canine mesenteric arteries.
    Author: Zhang JX, Okamura T, Toda N.
    Journal: Eur J Pharmacol; 1996 Sep 12; 311(2-3):169-76. PubMed ID: 8891597.
    Abstract:
    Transmural electrical stimulation (5-30 Hz) produced a frequency-dependent increase in the perfusion pressure of isolated, perfused dog mesenteric artery segments, which was suppressed by prazosin and abolished by tetrodotoxin. Treatment with endothelin-1 in low concentrations (10(-10) and 3 x 10(-10) M) inhibited the response to electrical nerve stimulation. The effect was not affected by NG-nitro-L-arginine, indomethacin and removal of the endothelium. The endothelin-1-induced inhibition was antagonized by 10(-7) M BQ123[cyclo(D-Trp-D-Asp-L-Pro-D-Val-L-Leu-)sodium], an endothelin ETA receptor antagonist, but not by 10(-5) M BQ788 [N-cis-2,6-dimethyl-piperidinocarbonyl-L- gamma-methylleucyl-D-1-methoxycarbonyltryptophanyl-D-norleuc ine], an antagonist of endothelin ETB1 and ETB2 receptors. IRL1620 [Suc-[Glu9, Ala11,15]endothelin-1-(8-21)], a selective endothelin ETB1 receptor agonist, did not alter the response to electrical stimulation. However, raising the concentration of endothelin-1 to 10(-9) M or higher potentiated the response. Similar results were also obtained in mesenteric artery strips in response to electrical stimulation. Endothelin-1 at low concentrations did not alter the contraction caused by exogenous norepinephrine in the artery strips, whereas the peptide at high concentrations potentiated the response. 3H-overflow evoked by transmural electrical stimulation from tissues prelabeled with [3H]norepinephrine was decreased by endothelin-1 (3 x 10(-10) M) in the superfused dog mesenteric arteries. It is concluded that endothelin-1 at low concentrations activates prejunctional endothelin ETA receptors and inhibits adrenergic nerve-mediated contractions by an inhibition of amine release, whereas the peptide at high concentrations potentiates the neurally induced contractions by a postjunctional enhancement, via endothelin ETA receptors, of the action of norepinephrine. Low concentrations of endothelin-1 appear to act as a vasodilator in adrenergically innervated mesenteric artery
    [Abstract] [Full Text] [Related] [New Search]