Physiology Department, University of Cincinnati, Cincinnati, OH, 45267-0576, USA.
Mol Cell Endocrinol. 2022 Jul 1;551:111674. doi: 10.1016/j.mce.2022.111674. Epub 2022 May 11.
Homeostasis during lactation is a special case in which the unit for regulation is a dyad comprising the mother and her currently nursing offspring (the mother-offspring dyad). This arrangement is not a trivial. A litter of mice can have a mass greater than the mother and nutrient demands that far exceed her. Homeostasis for milk secretion, appetite, and calcium metabolism must come under integrated control, responding seamlessly to the needs of the mother and the offspring. Serotonin (5-HT) is a primary local regulator of mammary homeostasis. 5-HT synthesis in the mammary epithelium is high during lactation and increases during milk stasis. Two important functions are attributed to the 5-HT system. Firstly, when alveolar spaces are filled with milk 5-HT inhibits milk secretion and opens tight junctions. This feedback induces early phases of involution. Secondly, 5-HT induces synthesis and secretion of parathyroid hormone-related peptide (PTHrP).
哺乳期的体内平衡是一种特殊情况，其调节单位是由母亲及其当前哺乳的后代（母子对）组成的对偶体。这种安排并非微不足道。一窝老鼠的体重可能超过母亲，而且营养需求远远超过母亲。乳汁分泌、食欲和钙代谢的体内平衡必须受到综合控制，无缝响应母亲和后代的需求。5-羟色胺（5-HT）是乳腺体内平衡的主要局部调节剂。哺乳期乳腺上皮细胞中的 5-HT 合成量很高，并且在乳汁停滞时增加。5-HT 系统具有两个重要功能。首先，当肺泡空间充满乳汁时，5-HT 会抑制乳汁分泌并打开紧密连接。这种反馈会诱导早期的 involution 阶段。其次，5-HT 会诱导甲状旁腺激素相关肽（PTHrP）的合成和分泌。
