Physiology and Pharmacology of BRS3 (Bombesin Receptor Subtype-3)

2022财年的进展包括： 2021年，我们发现表达Brs3(POA-Brs3)的视前区神经元的激活会提高体温；相反，这些神经元的急性抑制会降低体温。投射到下丘脑室旁核或下丘脑背内侧的POA-Brs3神经元通过交感神经系统增加体温、心率和血压。POA-Brs3神经元的长期失活导致体温变异性增加，体温设定点的增加和降低都超调，RNA表达谱表明POA-Brs3神经元有多种类型。因此，POA-Brs3神经元群体调节体温和心率，有助于寒冷防御，并微调体温的反馈控制。这些发现促进了对恒温的理解，恒温是哺乳动物生物学的一个定义特征。

Progress in FY2022 includes the following: In 2021 we identified preoptic area neurons expressing BRS3 (POA-BRS3) as a population whose activation increased body temperature; inversely, acute inhibition of these neurons reduced body temperature. POA-BRS3 neurons that project to either the paraventricular nucleus of the hypothalamus or the dorsomedial hypothalamus increased body temperature, heart rate, and blood pressure via the sympathetic nervous system. Long-term inactivation of POA-BRS3 neurons caused increased body temperature variability, overshooting both increases and decreases in body temperature set point, with RNA expression profiles suggesting multiple types of POA-BRS3 neurons. Thus, POA-BRS3 neuronal populations regulate body temperature and heart rate, contribute to cold defense, and fine-tune feedback control of body temperature. These findings advance understanding of homeothermy, a defining feature of mammalian biology.