Abstract
The stainless steel cannula inserting method was used to investigate the effects of acetaldehyde on isolated and perfused dog mesenteric arteries. Acetaldehyde when intraluminally administered induced a marked vasoconstriction, but repetitive injections of acetaldehyde caused tachyphylaxis. Acetaldehyde-induced vasoconstrictions were blocked by bunazosin, an alpha-1 adrenoceptor antagonist. After tyramine treatment, the acetaldehyde-induced constriction was consistently restored temporarily. It is suggested that tyramine may induce a release of norepinephrine mostly from the vesicle to the neuronal cytosol, and acetaldehyde may cause a release of norepinephrine from the cytosol to the extracellular space in the isolated canine mesenteric artery.
