Kajo van der
Marel1, Judith R. Homberg2, Willem M. Otte1,
Rick M. Dijkhuizen1
1Image Sciences Institute, University
Medical Center Utrecht, Utrecht, Netherlands; 2Donders Centre for
Neuroscience, UMC St. Radboud, Nijmegen, Netherlands
Genetic
variation in the serotonin transporter gene (5-HTTLPR) has been linked to
various neuropsychiatric disorders, including depression and drug addiction.
In this study we combined resting-state fMRI (rs-fMRI) with pharmacological
fMRI (phMRI) in the serotonin transporter knock-out rat, to study the effects
of disrupted serotonin homeostasis on functional organization during baseline
and psychoactive stimulation. With rs-fMRI we observed positive functional
connectivity among ROIs within the limbic system, but no difference with
controls. With phMRI we found stronger activation responses to cocaine in
knock-outs in specific limbic areas, which is in agreement with previously
reported cocaine supersensitivity.