Department of Bioregulation, Institute for Advanced Medical Science, Nippon Medical School, Kawasaki, 211-8533, Japan.
Department of Physiology, Jichi Medical University, Shimotsuke, Tochigi, 329-0498, Japan.
Sci Rep. 2021 Feb 8;11(1):3348. doi: 10.1038/s41598-021-82773-5.
Multiple sequential actions, performed during parental behaviors, are essential elements of reproduction in mammalian species. We showed that neurons expressing melanin concentrating hormone (MCH) in the lateral hypothalamic area (LHA) are more active in rodents of both sexes when exhibiting parental nursing behavior. Genetic ablation of the LHA-MCH neurons impaired maternal nursing. The post-birth survival rate was lower in pups born to female mice with congenitally ablated MCH neurons under control of tet-off system, exhibiting reduced crouching behavior. Virgin female and male mice with ablated MCH neurons were less interested in pups and maternal care. Chemogenetic and optogenetic stimulation of LHA-MCH neurons induced parental nursing in virgin female and male mice. LHA-MCH GABAergic neurons project fibres to the paraventricular hypothalamic nucleus (PVN) neurons. Optogenetic stimulation of PVN induces nursing crouching behavior along with increasing plasma oxytocin levels. The hypothalamic MCH neural relays play important functional roles in parental nursing behavior in female and male mice.
多种连续的动作，在亲代行为中执行，是哺乳动物物种繁殖的重要组成部分。我们发现，当表现出亲代哺乳行为时，表达黑色素浓缩激素（MCH）的神经元在两性啮齿动物的外侧下丘脑区域（LHA）中更加活跃。LHA-MCH 神经元的遗传消融会损害母性哺乳。在雌性小鼠中，通过 tet-off 系统出生的具有先天性消融 MCH 神经元的小鼠，其出生后存活率较低，表现出蜷缩行为减少。具有消融 MCH 神经元的处女雌性和雄性小鼠对幼鼠和母性照顾的兴趣降低。LHA-MCH 神经元的化学遗传和光遗传刺激诱导处女雌性和雄性小鼠进行亲代哺乳。LHA-MCH GABA 能神经元投射纤维到室旁下丘脑核（PVN）神经元。光遗传刺激 PVN 会诱导哺乳蜷缩行为，并增加血浆催产素水平。下丘脑 MCH 神经中继在雌性和雄性小鼠的亲代哺乳行为中发挥着重要的功能作用。
