Downregulation of Brain Phosphodiesterase Type IV Measured with 11C-(R)-Rolipram Positron Emission Tomography in Major Depressive Disorder
Biological Psychiatry, 06/08/2012
Fujita M et al. – This study is the first to demonstrate that brain levels of PDE4, a critical enzyme that regulates cyclic adenosine monophosphate, are decreased in unmedicated individuals with major depressive disorder in vivo.
Methods- 11C-(R)-Rolipram brain positron emission tomography scans were performed in 28 unmedicated MDD subjects and 25 age- and gender-matched healthy control subjects.
- Patients were moderately depressed and about one half were treatment-naive.
- 11C-(R)-Rolipram binding in the brain was measured using arterial 11C-(R)-rolipram levels to correct for the influence of cerebral blood flow.
- Major depressive disorder subjects showed a widespread, approximately 20% reduction in 11C-(R)-rolipram binding (p = .002), which was not caused by different volumes of gray matter.
- Decreased rolipram binding of similar magnitudes was observed in most brain areas.
- Rolipram binding did not correlate with the severity of depressive or anxiety symptoms.
