Neuronal Control of Metabolism group, Max Planck Institute for Metabolism Research, Cologne, Germany.
Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Cologne, Germany.
JCI Insight. 2022 Nov 8;7(21):e162753. doi: 10.1172/jci.insight.162753.
Dopamine acts on neurons in the arcuate nucleus (ARC) of the hypothalamus, which controls homeostatic feeding responses. Here we demonstrate a differential enrichment of dopamine receptor 1 (Drd1) expression in food intake-promoting agouti related peptide (AgRP)/neuropeptide Y (NPY) neurons and a large proportion of Drd2-expressing anorexigenic proopiomelanocortin (POMC) neurons. Owing to the nature of these receptors, this translates into a predominant activation of AgRP/NPY neurons upon dopamine stimulation and a larger proportion of dopamine-inhibited POMC neurons. Employing intersectional targeting of Drd2-expressing POMC neurons, we reveal that dopamine-mediated POMC neuron inhibition is Drd2 dependent and that POMCDrd2+ neurons exhibit differential expression of neuropeptide signaling mediators compared with the global POMC neuron population, which manifests in enhanced somatostatin responsiveness of POMCDrd2+ neurons. Selective chemogenetic activation of POMCDrd2+ neurons uncovered their ability to acutely suppress feeding and to preserve body temperature in fasted mice. Collectively, the present study provides the molecular and functional characterization of POMCDrd2+ neurons and aids our understanding of dopamine-dependent control of homeostatic energy-regulatory neurocircuits.
多巴胺作用于下丘脑弓状核(ARC)中的神经元,控制着体内平衡的摄食反应。在这里,我们证明了多巴胺受体 1(Drd1)在促进摄食的刺鼠相关肽(AgRP)/神经肽 Y(NPY)神经元和大量表达厌食性 proopiomelanocortin(POMC)神经元中的表达存在差异。由于这些受体的性质,这意味着多巴胺刺激时主要激活 AgRP/NPY 神经元,而多巴胺抑制的 POMC 神经元比例更大。通过对表达 Drd2 的 POMC 神经元进行交差靶向,我们揭示了多巴胺介导的 POMC 神经元抑制依赖于 Drd2,并且与全局 POMC 神经元群体相比,POMCDrd2+神经元表现出不同的神经肽信号转导介质的表达,这表现在 POMCDrd2+神经元对生长抑素的反应增强。选择性化学遗传学激活 POMCDrd2+神经元揭示了它们在急性抑制摄食和在禁食小鼠中维持体温的能力。总的来说,本研究提供了 POMCDrd2+神经元的分子和功能特征,并帮助我们理解多巴胺依赖的体内平衡能量调节神经回路的控制。