Role of Serotonin Transporter Changes in Depressive Responses to Sex-Steroid Hormone Manipulation: A Positron Emission Tomography Study.

Background: An adverse response to acute and pronounced changes in sex-hormone levels during, for example, the perimenopausal or postpartum period appears to heighten risk for major depression in women. The underlying risk mechanisms remain elusive but may include transiently compromised serotonergic brain signaling. Here, we modeled a biphasic ovarian sex hormone fluctuation using a gonadotropin-releasing hormone agonist (GnRHa) and evaluated if emergence of depressive symptoms was associated with change in cerebral serotonin transporter (SERT) binding following intervention.

Serotonin 2A receptor agonist binding in the human brain with [¹¹C]Cimbi-36.

[(11)C]Cimbi-36 was recently developed as a selective serotonin 2A (5-HT(2A)) receptor agonist radioligand for positron emission tomography (PET) brain imaging. Such an agonist PET radioligand may provide a novel, and more functional, measure of the serotonergic system and agonist binding is more likely than antagonist binding to reflect 5-HT levels in vivo. Here, we show data from a first-in-human clinical trial with [(11)C]Cimbi-36.

Trait aggression and trait impulsivity are not related to frontal cortex 5-HT2A receptor binding in healthy individuals.

Numerous studies indicate that the serotonergic (5-HT) transmitter system is involved in the regulation of impulsive aggression and there is from post-mortem, in vivo imaging and genetic studies evidence that the 5-HT2A receptor may be involved. We investigated 94 healthy individuals (60 men, mean age 47.0±18.