BRD2 and major depressive disorder: We assessed central noradrenaline transporter (NAT) availability using positron emission tomography (PET) and the NAT selective radiotracer S,S-[11C]O-methylreboxetine in immunotherapy-naïve patients with relapsing–remitting MS (RRMS; n = 11) compared to healthy controls (HC; n = 12), and its association to lesion load, time since manifestation, the expanded disability status scale (EDSS), the fatigue scale Würzburger Erschöpfungsinventar bei MS (WEIMuS) and Beck Depression Inventory (BDI).