Subchapter 93C – Thyronamines

Thyronamines (TAMs), which may be derived from thyroid hormones (THs) by deiodination and decarboxylation, are biologically active trace amines. Among nine TAMs, 3-T1AM is the most potent one. TAMs induce effects opposite to those of THs within minutes or hours: lowering body temperature; metabolic depression; and reduction in cardiac performance. A possible candidate receptor is trace amine-associated receptor 1 (TAAR1), a recently identified G protein-coupled receptor that is highly homologous to classical biogenic amine receptors including adrenergic, dopaminergic, and serotonergic receptors. Another candidate is α2A adrenergic receptor (ARA2A). A concerted role of TAAR1 and ARA2A in TAM actions is proposed. TAMs-induced hypothermia may have beneficial effects on neuroprotection or cardioprotection against stroke injury.