Abstract

A great deal of interest has recently focused upon the mechanism(s) associated with the generation and action of endothelium-derived relaxant factors (EDRFs) in blood vessels. Since we have shown that extracellular magnesium ions ([Mg2+]o) are important in control of coronary vascular tone and reactivity, we wondered whether these divalent cations play any role in the generation or action of EDRF in coronary arterial smooth muscle. Using isolated canine coronary arterial rings, we have now found that removal of [Mg2+]o inhibits the ability of these vascular preparations to relax when challenged with acetylcholine; in the absence of [Mg2+]o, the relaxation concentration-response curves for acetylcholine are shifted markedly to higher concentrations with small maxima. It, thus, appears that [Mg2+]o is an important co-factor for acetylcholine-induced endothelium-dependent relaxation in canine coronary arteries. These findings support our previous hypothesis that dietary deficiency of Mg may be an important factor in aetiology of coronary vasospasm.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.