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: Local anesthetic drugs reduce endothelium-dependent relaxations of porcine ciliary arteries.
    Author: Meyer P, Flammer J, Lüscher TF.
    Journal: Invest Ophthalmol Vis Sci; 1993 Aug; 34(9):2730-6. PubMed ID: 8344795.
    Abstract:
    PURPOSE: During retrobulbar anesthesia ocular hemodynamics are altered. The purpose of this study is to investigate the effects of local anesthetics in isolated porcine ciliary arteries (diameter between 200 and 400 microns). METHODS: Isolated porcine ciliary arteries were suspended in myograph systems filled with modified Krebs-Ringer solution for isometric tension recording. RESULTS: In quiescent or serotonin-precontracted arteries, lidocaine, bupivacaine, or mepivacaine (10(-9)-10(-5)M) evoked no change in vascular tone. However, all local anesthetics (10(-5)M) and bupivacaine (10(-5)-10(-6)M) reduced endothelium-dependent relaxations to bradykinin (10(-9)-10(-6)M), whereas the endothelium-independent relaxations to the nitric oxide-donor 3-morpholino-sydnonimine (SIN-1; 10(-9)-10(-5)M) were unaffected by local anesthetics. The addition of L-arginine (10(-4)M) markedly reduced the inhibitory effects of bupivacaine on endothelial vasodilatation function. CONCLUSION: These findings demonstrate that in porcine ciliary arteries, local anesthetics impair endothelial formation of nitric oxide from L-arginine after stimulation with bradykinin, which may contribute importantly to the reduction in blood flow to the eye during retrobulbar anesthesia.
    [Abstract] [Full Text] [Related] [New Search]