Neuromodulation of frontal and temporal cortex by intravenous d-fenfluramine: an [15O]H2O PET study in humans.
This study assessed the modulatory effect of a serotonergic agonist, d-fenfluramine, on localized neuronal firing as indexed by changes in regional cerebral blood flow (rCBF). Previously, we reported the effect of oral d, l-fenfluramine on neuronal activity as measured by change in [18F]fluorodeoxyglucose uptake. Improvements in the current study include: a more specific serotonin agonist, d-fenfluramine; a more reliable administration route, intravenous; and a one session paradigm made possible with the radiotracer [15O]H2O. Changes in relative rCBF (P < 0.001) were observed: increases within the frontal cortex bilaterally and decreases within the temporal cortex bilaterally, and left thalamus. Other significant findings were elevated cortisol and growth hormone; increased euphoria and panic symptoms and decreased tiredness. These results support further investigation with intravenous d-fenfluramine to study the net functional effects of serotonergic stimulation in health and illness.
Meyer
J H
JH
Clarke Institute of Psychiatry, Department of Psychiatry, University of Toronto, Ontario, Canada. meyerj@cs.clarke-inst.on.ca
Kapur
S
S
Wilson
A A
AA
DaSilva
J N
JN
Houle
S
S
Brown
G M
GM
D000328:Adult; D000818:Animals; D001519:Behavior / Q000187:drug effects*; D005260:Female; D005277:Fenfluramine / Q000494:pharmacology*; D005625:Frontal Lobe / Q000098:blood supply / Q000000981:diagnostic imaging / Q000187:drug effects*; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D010104:Oxygen Radioisotopes; D018490:Serotonin Agents / Q000494:pharmacology*; D013702:Temporal Lobe / Q000098:blood supply / Q000000981:diagnostic imaging / Q000187:drug effects*; D014055:Tomography, Emission-Computed
D010104:Oxygen Radioisotopes; D018490:Serotonin Agents; D005277:Fenfluramine; D013006:Growth Hormone; D006854:Hydrocortisone