Keeping it cool: Elucidating the actions of thyronamines in thermoregulation and cardiovascular function

3-碘甲状腺原胺(3-T1AM)是一种内源性生物活性降温物质，其药理作用与经典的致热甲状腺激素(TH)T3相反。给小鼠注射药理剂量的3-T1AM会导致严重的体温过低和心动过缓。到目前为止，这些效应背后的机制仍然难以捉摸。鉴于TH可以集中作用于体温调节和心血管功能这一新概念，我们假设3-T1AM也影响棕色脂肪产热和心脏功能的中枢自主控制。因此，本项目旨在利用新的活体技术(如红外相机、无线电遥测、血压测量、立体定向注射)来揭示这些机制，以研究3-T1AM及其代谢产物在完整动物体内的作用。对3-T1AM作用的细胞和组织定位和表征将有助于阐明其潜在的分子机制。综上所述，该研究将有助于更好地了解甲状腺激素和甲状腺激素代谢的平衡和生理动态平衡。

3-Iodothyronamine (3-T1AM) is an endogenous and biologically active cooling substance whose pharmacological actions are opposite to those induced by the classical thermogenic thyroid hormone (TH) T3. Pharmacological doses of 3-T1AM injected into mice lead to profound hypothermia and bradycardia. To date, the mechanisms underlying these effects are still elusive. Given the novel concept that TH can act centrally on thermoregulation and cardiovascular function, we hypothesize that 3-T1AM also affect the central autonomic control of brown fat thermogenesis and heart function. Thus, this project aims to unravel these mechanisms using novel in vivo techniques (e.g. infrared camera, radiotelemetry, blood pressure measurements, stereotaxic injections) to investigate the effect of 3-T1AM and its metabolites in the intact animal. The cellular and tissue localization and characterization of 3-T1AM actions will help to elucidate the underlying molecular mechanisms. In summary, the study will contribute to a better understanding of the counterbalance and physiological homeostasis of thyroid hormone and thyronamine metabolism.