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

Search MEDLINE/PubMed


  • Title: Endothelial modulation of 5-hydroxytryptamine-induced contraction in goat cerebral arteries.
    Author: Miranda FJ, Torregrosa G, Salom JB, Alabadí JA, Jover T, Barberá MD, Alborch E.
    Journal: Gen Pharmacol; 1993 May; 24(3):649-53. PubMed ID: 8365646.
    Abstract:
    1. In isolated goat middle cerebral artery segments, 5-hydroxytryptamine (5-HT, 10(-8) -3 x 10(-5)M) caused concentration-dependent contractions, with EC50 = 2.1 (1.9-2.5) x 10(-7) M and Emax = 60 +/- 2% of 50 mM KCl-induced contraction. 2. Mechanical removal of endothelium significantly increased the Emax (91 +/- 8%) and did not change the EC50 value of 5-HT-elicited contractions. 3. Incubation of unrubbed arteries with the irreversible inhibitor of EDRF, gossypol (10(-5) M), significantly increased the contractile response to 5-HT (Emax = 77 +/- 4%). 4. Incubation of unrubbed arteries with the competitive inhibitor of the NO synthesis, NG-nitro-L-arginine (L-NOARG) (10(-5) M), significantly enhanced the arterial response to 5-HT (Emax = 71 +/- 5%). The effects of L-NOARG were reversed by L-arginine (10(-4) M) but not by D-arginine (10(-4) M). 5. Pretreatment with the inhibitor of cyclooxygenase, indomethacin (10(-5) M), significantly increased the response of unrubbed arteries to 5-HT, with an Emax of 69 +/- 3%. 6. These results suggest that endothelium modulates the constrictor effect of 5-HT in goat cerebral arteries by producing both EDRF, probably NO, and prostacyclin.
    [Abstract] [Full Text] [Related] [New Search]