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: Alpha 1- and alpha 2-adrenoceptors at different levels of the canine saphenous vein.
    Author: Guimarães S, Moura D, Nunes JP, Vaz-da-Silva MJ, Guimarães JT.
    Journal: J Neural Transm Suppl; 1991; 34():163-9. PubMed ID: 1667869.
    Abstract:
    Presynaptic alpha2- and postsynaptic alpha1-adrenoceptors were compared at the distal and proximal parts of the dog saphenous vein. The results obtained show that: (1) yohimbine is more effective against postsynaptic responses to phenylephrine distally than proximally. On the contrary, WB-4101 is more effective proximally; (2) phenylephrine increases inositol monophosphate production at both levels, but the increase is more pronounced distally; (3) UK-14, 304 and adrenaline reduce and yohimbine and phentolamine increase the release of 3H-noradrenaline caused by electrical stimulation at both levels. However, while adrenaline as well as the antagonists are equipotent at the two levels, UK-14,304 is more potent distally than proximally. In conclusion, we suggest that: more alpha 1A-adrenoceptors exist distally than proximally; imidazoline sites can exist at the distal level which contribute to the higher potency of UK-14,304 distally.
    [Abstract] [Full Text] [Related] [New Search]