title: Antagonism by Ca2+ of the inhibitory action of PGE1 on the electrically induced vasoconstriction in the rabbit ear artery.
abstract: The inhibitory action of PGE1 on vasoconstrictor responses to nerve stimulation of isolated ear arteries of rabbits was studied in the presence of 1.0 to 7.5 mM external calcium concentration. Raising the [Ca]0 in the medium increased the electrically induced vasoconstriction and antagonized the inhibitory effect of PGE1 on constrictor responses. This antagonism is probably due to an interaction between Ca2+ and PGE1 in the sympathetic nerves to the vessel.
mesh_terms: D000818:Animals; D001158:Arteries / Q000187:drug effects / Q000502:physiology; D002118:Calcium / Q000494:pharmacology*; D004558:Electric Stimulation; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D011458:Prostaglandins E / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D011817:Rabbits; D009435:Synaptic Transmission / Q000187:drug effects; D014666:Vasomotor System / Q000187:drug effects*
chemical_list: D011458:Prostaglandins E; D002118:Calcium