3-Monoiodothyronamine: The rationale for its action as an endogenous adrenergic-blocking neuromodulator

► 3-Monoiodothyronamine (T1AM) is the first known metabolite of the thyroid hormone reverse triiodothyronine: ► Activates the locus coeruleus in physiological concentrations. ► Acts in vivo as a beta adrenergic blocker. ► Has a chemical structure and in vivo actions that point to a role in the noradrenergic nervous system. ► May activate cAMP.