Prejunctional effects of 5-hydroxytryptamine on noradrenergic nerves in the cardiovascular system.
Recent studies indicate that some peripheral noradrenergic nerves have specific 5-hydroxytryptamine (5-HT) receptors on their terminals that can mediate inhibition of release of transmitter after neuronal stimulation. It is now also known that 5-HT will cause norepinephrine release from noradrenergic nerve terminals in the isolated rabbit heart by a receptor mechanism. The evidence for the existence of these two types of prejunctional 5-HT receptor is discussed together with findings to date on their distribution and possible functional importance in the whole animal. In addition 5-HT has weak sympathomimetic actions, which result from its ability to interact with noradrenergic removal processes. The displaced transmitter can then interact with adrenoceptors situated pre- or postjunctionally.
D000818:Animals; D002319:Cardiovascular System / Q000294:innervation*; D004558:Electric Stimulation; D008995:Monoamine Oxidase / Q000378:metabolism; D009130:Muscle, Smooth / Q000378:metabolism; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D009638:Norepinephrine / Q000378:metabolism*; D012701:Serotonin / Q000494:pharmacology*
D012701:Serotonin; D008995:Monoamine Oxidase; D009638:Norepinephrine