Lakshmanan J, Beri U, Perheentupa J, Grueters A, Kim H, Macaso T, Fisher D A
J Neurosci Res. 1984;12(1):71-85. doi: 10.1002/jnr.490120107.
The growth of the submandibular gland (SMG) was studied in newborn mice from birth to 15 days of age. Progressive changes in wet weight were observed to accompany changes in biochemical constituents such as RNA, protein, and lipid. Thyroxine (T4) administration from days 0-6 produced changes in SMG growth and SMG accumulation of RNA, protein, and lipid components relative to control pups treated with a similar volume of vehicle. This hormone regimen produced no measurable changes in SMG nerve growth factor (SMG-NGF) concentration. T4 responsiveness also was studied from days 0-15. Three patterns of T4 injection (from days 0-6, 7-14, and 0-14) were found to elicit a differential response in the three biochemical constituents measured, but treatment from days 7-14 and 0-14 elicited precocious increments in SMG-NGF concentrations on day 15. The effect of T4 injection from birth was more effective in augmenting SMG-NGF concentration than hormone treatment initiated from days 7-14. A persistent T4 effect on SMG-NGF also was observed on day 21 following hormone treatment from days 7-14 or 0-14. In summary, the acquisition of SMG-NGF responsiveness to T4 appears to develop during the neonatal period. The administration of T4 during this period also precociously stimulates the mechanisms that govern the normal ontogeny of SMG-NGF at the time of weaning.
研究了新生小鼠从出生到15日龄下颌下腺（SMG）的生长情况。观察到湿重的渐进性变化伴随着RNA、蛋白质和脂质等生化成分的变化。在第0 - 6天给予甲状腺素（T4），相对于用相同体积载体处理的对照幼崽，T4使SMG的生长以及RNA、蛋白质和脂质成分的积累发生了变化。这种激素处理方案在SMG神经生长因子（SMG - NGF）浓度上未产生可测量的变化。还研究了第0 - 15天T4的反应性。发现三种T4注射模式（第0 - 6天、第7 - 14天和第0 - 14天）在测量的三种生化成分中引发了不同的反应，但第7 - 14天和第0 - 14天的处理在第15天引起了SMG - NGF浓度的早熟增加。从出生开始注射T4在增加SMG - NGF浓度方面比从第7 - 14天开始的激素处理更有效。在第7 - 14天或第0 - 14天进行激素处理后，在第21天也观察到T4对SMG - NGF的持续影响。总之，SMG - NGF对T4的反应性似乎在新生儿期发展。在此期间给予T4还早熟地刺激了在断奶时控制SMG - NGF正常个体发育的机制。
