At present, there are many studies on neural circuit mechanisms underlying individual behaviors. In contrast, there are few studies on how animals coordinate multiple behaviors, in particular to balance individual needs and prorogation of the species.

　　On November 20th, the "Journal of Neuroscience" published a research paper entitled "Agrp neurons project to the medial preoptic area and modulate maternal nest-building". This study was conducted by the team of XU Xiao-Hong in the Institute of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology of the Chinese Academy of Sciences and the State Key Laboratory of Neuroscience. In this study, the team explored the mutual antagonism between hunger and maternal behaviors, as well as the neural basis for such behavioral interactions.

　　They found that: 1. Agrp neurons, which are essential for feeding, form inhibitory synapses onto a subset of neurons in the medial preoptic area (mPOA), which controls maternal behavior; 2. Optogenetic activation of Agrp neurons specifically reduces maternal nest-building behavior without affecting pup retrieval, partially mimicking the inhibitory effects of hunger on maternal behaviors; 3. Optogenetic stimulation of Agrp neural projections to the mPOA also specifically inhibits maternal nest-building while stimulating Agrp neural projections to the lateral hypothalamus has no effects on maternal behaviors; 4. The neurons in the mPOA that receive Agrp neural projection are Vgat+; 5. Optogenetic or chemogenetic inhibition of mPOA Vgat+ neurons also inhibits maternal nest-building; 6. Neuronal ensembles that underlie maternal nest-building are likely to be distinct from those that underlie pup retrieval. Together with previous findings from the lab about pup suppression of hunger (Han et al., Neuroscience, 2017) and the role of mPOA Esr1+ neurons in pup retrieval (Wei et al., Nature Communications, 2018), the authors proposes a model where reciprocal antagonism coordinate hunger-induced feeding and various components of maternal behaviors (Fig. 1).

　　This work was carried out by Graduate Students LI Xing-Yu and HAN Ying together with assistant investigator ZHANG Wen from the XU’s lab. Experiments on body temperature measurement was done in collaboration with Dr. SHEN Wei’s lab in Shanghai Tech University. Other students of the XU’s lab also participated in the project. This work was funded by the National Natural Science Foundation of China (31471065, 31771169) and the Strategic Science and Technology Special Project of the Chinese Academy of Sciences (XDB02030005, XDBS01010200).

　　Figure 1. A model on reciprocal antagonisms between hunger and maternal care. Agrp neurons promote feeding; mPOA Vgat+Esr1+neurons promote pup retrieval and Vgat+Esr1-neurons are more important for maternal nest-building. Activation of Agrp neurons during hunger results in elevated inhibition of mPOA Vgat+ neurons and suppression of maternal nest-building but not pup retrieval while in parallel activation of mPOA Vglut2+ neurons by pup derived cues delays and inhibits feedings. 3V, third ventricle; acp, anterior commissure, posterior, Arc, arcuate nucleus; mPOA, medial preoptic area.