Pharmacological Evidence for the Existence of Multiple Functional Pools of Brain Serotonin: Analysis of Brain Perfusate From Conscious Rats

Publisher Website
Google Scholar
Abstract
The serotonin reuptake inhibitor fluoxetine significantly reduced levels of endogenous 5-hydroxyindoleacetic acid (5-HIAA) in brain perfusate of rats implanted with push-pull cannulas. This occurred in conjunction with its suppressant effect upon fixed-ratio operant behavior. Behavior suppressed with the serotonin agonist lysergic acid diethylamide (LSD) occurred in conjunction with a reduction of 5-HIAA only after 5-HIAA was elevated, shortly before, by 5 mg/kg of the serotonin precursor 5-hydroxytryptophan. Our data demonstrate the likely existence of multiple functional pools of serotonin in brain and support the notion that LSD preferentially affects a newly synthesized pool of this transmitter.