Robberecht W, Denef C
Laboratory of Cell Pharmacology, School of Medicine, University of Leuven, Belgium.
Cell Biol Int Rep. 1990 Nov;14(11):1001-11. doi: 10.1016/0309-1651(90)90112-c.
In anterior pituitary cell aggregates cultured in the presence of the glucocorticoid dexamethasone (DEX) angiotensin II (AII) had a dual effect on growth hormone (GH) release. The peptide stimulated the release in aggregates from 2-week-old rats, whereas the peptide had an inhibitory effect in cultures from adult rats. Treatment of aggregates from adult rats with pertussis toxin (PT) reversed the inhibitory effect of AII on GH release in a stimulatory effect; PT treatment of aggregates from 18- to 20-day-old rats significantly enhanced the stimulation of GH release by AII. The effect of PT was seen only when DEX was added to the culture medium. The present data suggest that the glucocorticoid-dependent stimulus-effect coupling of AII on GH release involves both a stimulatory and an inhibitory component, the latter being abolished by PT, and that the stimulatory component predominates during immature life while the inhibitory one during adult life.
在存在糖皮质激素地塞米松（DEX）的情况下培养的垂体前叶细胞聚集体中，血管紧张素II（AII）对生长激素（GH）释放具有双重作用。该肽刺激2周龄大鼠聚集体中的释放，而该肽对成年大鼠培养物具有抑制作用。用百日咳毒素（PT）处理成年大鼠的聚集体可将AII对GH释放的抑制作用逆转成刺激作用；用PT处理18至20日龄大鼠的聚集体可显著增强AII对GH释放的刺激作用。仅当将DEX添加到培养基中时才观察到PT的作用。目前的数据表明，AII对GH释放的糖皮质激素依赖性刺激-效应偶联涉及一个刺激成分和一个抑制成分，后者被PT消除，并且刺激成分在未成熟生命期间占主导，而抑制成分在成年生命期间占主导。
