Age, Sex, and Reproductive Hormone Effects on Brain Serotonin-1A and Serotonin-2A Receptor Binding in a Healthy Population

There is a need for rigorous positron emission tomography (PET) and endocrine methods to address inconsistencies in the literature regarding age, sex, and reproductive hormone effects on central serotonin (5HT) 1A and 2A receptor binding potential (BP). Healthy subjects ( n =71), aged 20–80 years, underwent 5HT1A and 2A receptor imaging using consecutive 90-min PET acquisitions with [ 11 C]WAY100635 and [ 18 F]altanserin. Logan graphical analysis was used to derive BP using atrophy-corrected distribution volume ( V T ) in prefrontal, mesiotemporal, occipital cortices, and raphe nucleus (5HT1A only). We used multivariate linear regression modeling to examine BP relationships with age, age 2 , sex, and hormone concentrations, with post hoc regional significance set at p