S U M M A R Y 1. Serotonin is present in blood vessels and the heart of the rat in concentrations of about one-sixth that of noradrenaline.2. The concentrations of serotonin are increased two-fold following treatment with the monoamine oxidase inhibitor, pargyline, and the elevation of levels is rapid.3. It is suggested that monoamine oxidase regulates the content of serotonin in blood vessels and the heart.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.