Abstract
The radioactive microsphere method has been used to study the effects of the infusions of 5-hydroxytryptamine (5-HT) on cardiac output and its distribution in both pentobarbital-anaesthetized and conscious rabbits. Doses of 5 and 10 μg kg −1 min −1 caused progressive decreases in diastolic pressure and total peripheral resistance in the anaesthetized rabbits but not in conscious ones. There was no significant effect on systolic pressure, cardiac output or heart rate. However, in spite of minimal systemic changes, in both groups 5-HT evoked increases in blood flow to the brain, heart and stomach at the expense of the kidneys, skin, liver (hepatic artery) and lungs (bronchial artery plus arteriovenous anaestomotic flow). The 10 μg kg −1 min −1 dose of 5-HT also increased blood flow and decreased resistance in the extracerebral tissues of the head. The significance of these findings in relation to the possible role of 5-HT in the migraine syndrome has been discussed.
Sign-in/Register to access full text options 
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 callDisclaimer: 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.
