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: Smooth-muscle effects of substance P.
    Author: Zamfirova R, Todorov S.
    Journal: Methods Find Exp Clin Pharmacol; 1988 Nov; 10(11):683-6. PubMed ID: 2464727.
    Abstract:
    The effects of substance P (SP) on smooth-muscle contractions induced by noradrenaline (NA) or by high- or low-frequency electrical stimulation (ES) were studied on isolated rat vas deferens and musculus anococcygeus. Neither the contractile effects of NA nor those of high-frequency ES were significantly changed by SP. The peptide in concentrations of 1 x 10(-7) M and 1 x 10(-6) M strongly potentiated (up to 70%) vas deferens contractions in response to low-frequency ES but slightly reduced those of musculus anococcygeus. Inhibition of the opiate receptors by 1 x 10(-6) M naloxone did not change the potentiating SP-effect on vas deferens contractions. Blockade of the prostaglandin (PG) receptors by polyphloretin phosphate (PPP), 5 micrograms/ml, or of the PGs synthesis by indomethacin, 5 x 10(-6) M, resulted in a slight increase of the SP-potentiating effect. The present results suggest that specific presynaptic SP-receptors (excitatory or inhibitory) play a major role in the mechanism of the potentiating action of substance P.
    [Abstract] [Full Text] [Related] [New Search]