Single-cell molecular and cellular architecture of neurohypophyseal cell types in adult mouse

The neurohypophysis (NH), located at the posterior lobe of the pituitary, is a major neuroendocrine tissue, which mediates osmotic balance, blood pressure, reproduction, and lactation by means of releasing the neurohormones oxytocin and arginine-vasopressin from the brain into the peripheral blood circulation. The major cellular components of the NH are hypothalamic axonal termini, fenestrated endothelia and pituicytes, the resident astroglia. However, despite the physiological importance of the NH, the exact molecular signature defining neurohypophyseal cell types and in particular the pituicytes, remains unclear. Using single cell RNA sequencing, we captured seven distinct cell types in the NH and intermediate lobe (IL) of adult male mouse. We revealed novel pituicyte markers showing higher specificity than previously reported markers. Multiplexing single molecule in situ hybridization revealed spatial organization of the major cell types implying intercellular communications. We present a comprehensive molecular and cellular characterization of neurohypophyseal cell-types serving as a valuable resource for further functional research. Overall design: 2 pools of 5 dissected neurohypophyses from 3-month-old male C57/BL6 mice were prepared for 10x Chromium single-cell RNA-Seq

位于垂体后叶的神经垂体（neurohypophysis, NH）是一类重要的神经内分泌组织，可通过将脑内的催产素（oxytocin）与精氨酸加压素（arginine-vasopressin）这两种神经激素释放至外周血液循环，调节机体渗透压平衡、血压、生殖功能与泌乳活动。神经垂体的主要细胞组分包括下丘脑轴突终末、有孔内皮细胞以及作为常驻星形胶质细胞的垂体细胞（pituicytes）。尽管神经垂体具有重要的生理功能，但界定神经垂体各类细胞（尤其是垂体细胞）的确切分子特征仍未明确。本研究通过单细胞RNA测序（single cell RNA sequencing），从成年雄性小鼠的神经垂体与中间叶（intermediate lobe, IL）中捕获了7种不同的细胞类型；我们鉴定出了特异性优于既往报道标记物的新型垂体细胞标记物。多重单分子原位杂交（single molecule in situ hybridization）技术揭示了主要细胞类型的空间排布模式，提示存在细胞间通讯。本研究对神经垂体细胞类型进行了全面的分子与细胞学特征解析，可为后续功能研究提供宝贵的参考资源。总体实验设计：将3月龄雄性C57/BL6小鼠的5个分离神经垂体分为2个混合样本，用于10x Chromium单细胞RNA测序（single-cell RNA-Seq）。