Yagil C, Naito Y, Barka T
Am J Anat. 1986 Sep;177(1):55-62. doi: 10.1002/aja.1001770107.
Administration of the beta-adrenergic drug isoproterenol (IPR) produces hyperplastic and hypertrophic enlargements of the submandibular gland of the rat and induces the synthesis of specific proteins in this organ. One of these proteins, the LM (large mobile) protein, was demonstrated immunocytochemically in the submandibular glands of developing untreated and IPR-treated rats. Immunoreactive LM protein was absent in the glands of 20-day-old fetuses and 1- and 2-day-old rats. It was localized in the proacinar and immature acinar cells in the glands of 6- to 21-day-old animals, but it was undetectable at 28 days of age. In the glands of adult rats, secretory granules of the granular convoluted tubule cells showed immunostaining for the LM protein which was also present in trace amounts in the acinar cells. Daily administration of IPR for 5 days to newborn or 8- or 15-day-old rats caused an apparent acceleration of proacinar/acinar cell differentiation, and consequently it increased the frequency of cells immunostained for the LM protein as well as the amount of immunoreactive material in these cells. Thus, the expression of LM protein in the submandibular gland is developmentally regulated, and it is restricted to the stage of differentiation of proacinar cells from terminal tubule cells. IPR is capable of inducing this protein in fully differentiated acinar cells in 3-week-old or older animals.
给予β-肾上腺素能药物异丙肾上腺素（IPR）会使大鼠下颌下腺出现增生性和肥大性增大，并诱导该器官中特定蛋白质的合成。其中一种蛋白质，即LM（大迁移）蛋白，在未处理和经IPR处理的发育中大鼠的下颌下腺中通过免疫细胞化学方法得以证实。在20日龄胎儿以及1日龄和2日龄大鼠的腺体中未检测到免疫反应性LM蛋白。在6至21日龄动物的腺体中，它定位于腺泡前体细胞和未成熟腺泡细胞中，但在28日龄时无法检测到。在成年大鼠的腺体中，颗粒曲管细胞的分泌颗粒显示出对LM蛋白的免疫染色，腺泡细胞中也有微量存在。对新生大鼠或8日龄或15日龄大鼠每日给予IPR，持续5天，会导致腺泡前体细胞/腺泡细胞分化明显加速，因此增加了对LM蛋白免疫染色的细胞频率以及这些细胞中免疫反应性物质的量。因此，下颌下腺中LM蛋白的表达受发育调控，并且仅限于腺泡前体细胞从终末小管细胞分化的阶段。IPR能够在3周龄或更大年龄动物的完全分化腺泡细胞中诱导这种蛋白质的产生。
