Dexamethasone induces advanced growth hormone expression in the fetal rat pituitary gland in vivo.
Dexamethasone induces advanced growth hormone expression in the fetal rat pituitary gland in vivo.
复制标题
地塞米松在体内诱导胎鼠垂体的高级生长激素表达。
DOI：
10.1210/endo.132.2.7678792
复制
发表时间：
1993
期刊：
影响因子：
4.8
通讯作者：
T. Tachibana
中科院分区：
文献类型：
--
作者：
H. Nogami;T. Tachibana
研究了地塞米松(DEX)对胎鼠脑垂体腺生长激素(GH)表达的影响。妊娠大鼠于孕16~19天口服地塞米松(25 mg/L)，连续40h后处死。DEX对正常胎儿GH细胞的诱导作用在第17天较弱，在第16天则不明显，第19天GH细胞数量增加一倍，GH抗血清对GH细胞的染色增强。原位杂交显示，18天时，地塞米松组胎儿脑垂体腺内可见大量生长激素信使核糖核酸(GH Messenger RNA，mRNA)阳性细胞，而与胎龄匹配的对照组仅有少量GH信使RNA阳性细胞。Northern印迹分析显示，DEX在第17天可诱导胎鼠脑下垂体内少量GH mRNA的积聚，而在第18天可诱导GH mRNA水平显著升高。17-19天给孕鼠注射美曲酮(饮水中0.5 mg/ml)可显著降低孕19天GH细胞的数量。短期注射DEX(在处死前18小时和6小时重复皮下注射)也能在第18天诱导出免疫阳性的GH细胞，但在第17天胎儿时未见。在连续注射地塞米松后40h内，仅在第17天出现免疫阳性的生长激素细胞，提示胎儿对地塞米松的敏感性在第17天和第18天之间存在差异。这些结果表明，在胎儿生命的早期阶段，地塞米松可以诱导免疫阳性的生长激素细胞和生长激素基因的表达。提示糖皮质激素在胎儿期垂体腺生长激素细胞的发育中起重要作用。
The effects of dexamethasone (DEX) on the onset of GH expression in the fetal rat pituitary gland were studied. Pregnant rats received oral administration of DEX dissolved in drinking water (25 mg/liter) for 40 h before killing on days 16-19 of pregnancy. The number of immunoreactive GH cells in the control fetus on day 18 was very small, whereas it was remarkably increased by DEX to a compatible value obtained from control fetuses on day 19. The effect of DEX on the induction of immunoreactive GH cells was found to be less potent on day 17 and not evident on day 16. The population of GH cells on day 19 was doubled, and they stained more intensely by GH antiserum after DEX treatment. In situ hybridization revealed that there were many GH messenger RNA (mRNA)-positive cells in the pituitary gland of a DEX-treated fetus at day 18, whereas they were negligible in number in the age-matched control. Northern blot analysis revealed that DEX induced accumulation of small amounts of GH mRNA in the fetal pituitary gland on day 17, whereas it induced a marked elevation of GH mRNA level on day 18. Reducing the levels of endogenous glucocorticoids by the administration of metyrapone (0.5 mg/ml in drinking water) to the pregnant rats from day 17-19 resulted in the significant reduction in the number of GH cells at day 19. Short-term treatment of DEX (duplicate sc injections at 18 h and 6 h before killing) also induced immunoreactive GH cells on day-18 fetuses but not on day-17 fetuses. Immunoreactive GH cells appeared on day 17 only after quadruplicate injections of DEX during last 40 h, suggesting that there is a difference in fetal sensitivity to DEX between days 17 and 18. These results indicate that immunoreactive GH cells and GH mRNA are inducible by DEX at an earlier stage of the fetal life than they normally appear. It is suggested that glucocorticoids play an important role in the development of GH cells in the fetal pituitary gland in vivo.
垂体功能减退症儿童的肾上腺雄激素对美替拉酮、促肾上腺皮质激素和促肾上腺皮质激素释放激素刺激的反应。
DOI：
10.1210/jcem-65-2-282
发表时间：
1987
期刊：
The Journal of clinical endocrinology and metabolism
影响因子：
--
作者：
Pang,SY;Legido,A;Levine,LS;Temeck,JW;New,MI
通讯作者：
New,MI
影响因子：
4.8
作者：
Khorram,O;DePalatis,LR;McCann,SM
通讯作者：
McCann,SM
影响因子：
2.7
作者：
COX, KH;DELEON, DV;ANGERER, RC
通讯作者：
ANGERER, RC