Early down-regulation of milk production after weaning by pup removal and prior to involution in mouse mammary glands.
Early down-regulation of milk production after weaning by pup removal and prior to involution in mouse mammary glands.
复制标题
断奶后通过去除幼仔而早期下调产奶量，并在小鼠乳腺退化之前进行早期下调。
DOI：
10.1007/s00441-014-2013-7
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发表时间：
2015
影响因子：
3.6
通讯作者：
Kobayashi K
中科院分区：
文献类型：
--
作者：
Uejyo T;Oyama S;Kuki T;Kumura H;Kobayashi K
乳腺是一个高度特化的器官，能够重复肺泡结构的发育和退化（退化）以产生乳汁。乳房退化包括两个阶段。第一阶段是可逆的，持续到小鼠断奶后约48小时。有趣的是，在退化的第一阶段开始之前，延长挤奶间隔可以改变肺泡上皮细胞（AEC）的乳汁分泌活性。在这项研究中，我们调查的AEC分泌牛奶的能力在退化过程中的变化。仔细观察切割的caspase-3阳性AEC的数量和位置发现，第一阶段的退化发生在断奶后约24 h，第二阶段开始于断奶后48和72 h之间。然而，最初的变化，在产奶能力的AEC开始断奶后1小时，产奶逐渐停止在24小时内。此外，STAT 3的激活和STAT 5的失活发生在一些AEC断奶后6小时，更广泛的24小时。此外，乳生产过程，如营养吸收，合成和分泌停止断奶后24小时。有趣的是，尽管与甘油三酯产生相关的基因（Srebp 1和AQP 3）的表达水平下调，但在断奶后12 h的AEC中观察到扩大的细胞质脂滴。这些结果表明，几个变化的产奶能力的AEC发生在扩大哺乳间隔和之前的复旧。
The mammary gland is a highly specialized organ that is able to repeat development and regression (involution) of alveolar structures for milk production. Mammary involution consists in two phases. The first phase is reversible and lasts until approximately 48 h after weaning in mice. Interestingly, an extended milking interval can change the milk-secretory activity of alveolar epithelial cells (AECs) before the first phase of involution begins. In this study, we investigate the changes in the ability of AECs to secrete milk during the involution progression. Careful observation of the number and locations of cleaved caspase-3 positive AECs revealed that the first phase of involution occurred approximately 24 h after weaning and the second phase began between 48 and 72 h after weaning. However, initial changes in the milk production ability of AECs began just 1 h after weaning and milk production gradually ceased within 24 h. In addition, activation of STAT3 and inactivation of STAT5 had occurred in some AECs by 6 h after weaning and more broadly by 24 h. In addition, milk production processes such as nutrient uptake, synthesis, and secretion ceased by 24 h post-weaning. Interestingly, enlarged cytoplasmic lipid droplets were observed in AECs 12 h after weaning even though the expression levels of genes relevant to triglyceride production (Srebp1andAQP3) were down-regulated. These results indicate that several changes in the milk production ability of AECs occur during expanded suckling intervals and prior to involution.