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: The inhibitory effects of vasoactive intestinal polypeptide on the mechanical and electrical activity of canine antral smooth muscle.
    Author: Morgan KG, Schmalz PF, Szurszewski JH.
    Journal: J Physiol; 1978 Sep; 282():437-50. PubMed ID: 722548.
    Abstract:
    1. The inhibitory effects of vasoactive intestinal polypeptide (VIP) on the electrical and mechanical activity of canine antral smooth muscle were investigated. 2. In concentrations ranging from 5 X 10(-9) to 1 X 10(-7) M, VIP decreased the force of spontaneous contractions but had no measurable effect on spontaneous action potential complexes. 3. VIP had no effect on the increase in the amplitude and duration of the plateau potential and on the amplitude of contraction caused by a maximally effective concentration of acetylcholine. 4. VIP caused a significant decrease in the force of contraction caused by ED50 and threshold concentrations of acetylcholine. However, VIP had no measurable effect on the increase in the size of the action potential plateau caused by either concentration of acetylcholine. 5. VIP antagonized the increase in the amplitude of the plateau potential and the force of contraction induced by pentagastrin. It had no consistent effect on the pentagastrin-induced increase in frequency. 6. The data indicate that VIP acts as an inhibitor in this tissue in two distinct ways. It uncouples electromechanical coupling during spontaneous and acetylcholine-induced electrical and mechanical activity, and antagonizes pentagastrin-induced increases in electrical and mechanical activities.
    [Abstract] [Full Text] [Related] [New Search]