Capacity for 5-HT1A-mediated autoregulation predicts amygdala reactivity

We examined the contribution of 5-HT1A autoreceptors ( with [ C-11] WAY100635 positron emission tomography) to amygdala reactivity ( with blood oxygenation level - dependent functional magnetic resonance imaging) in 20 healthy adult volunteers. We found a significant inverse relationship wherein 5-HT1A autoreceptor density predicted a notable 30 - 44% of the variability in amygdala reactivity. Our data suggest a potential molecular mechanism by which a reduced capacity for negative feedback regulation of 5-HT release is associated with increased amygdala reactivity.