Glucocorticoids stimulate the accumulation of lipids in the rat corpus luteum.
Glucocorticoids stimulate the accumulation of lipids in the rat corpus luteum.
复制标题
糖皮质激素刺激大鼠黄体中脂质的积累。
DOI：
10.1095/biolreprod61.2.416
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发表时间：
1999
影响因子：
3.6
通讯作者：
Keyes,PL
中科院分区：
文献类型：
--
作者：
Towns,R;Menon,KM;Brabec,RK;Silverstein,AM;Cohen,JM;Bowen,JM;Keyes,PL
我们研究了在垂体促性腺激素缺乏的情况下，糖皮质激素对大鼠黄体的营养作用的生理基础。向未成熟（第29天）Sprague-Dawley大鼠给予eCG和hCG以诱导黄体发育，并在第32天切除垂体。从第40天开始，大鼠接受每日两次s.c.注射地塞米松（dex; 200 μg/大鼠/天）或媒介物（对照），然后在第44天处死。dex给药大鼠的血浆20α-二氢孕酮（黄体产生的主要类固醇）高于（p≤ 0.01）对照大鼠（44.5 ± 2.3 vs. 23.0 ± 5.6 ng/ml）。地塞米松治疗增加了脂质滴和脂质在黄体所揭示的电子显微镜和油红O染色。与对照组相比，dex给药大鼠的黄体中胆固醇酯较高（分别为14.8 ± 1.1和2.2 ± 0.5 μg/mg黄体湿组织;p≤ 0.05）。另一组切除垂体的大鼠接受高剂量或低剂量的皮质酮治疗，与对照组相比，这两种剂量均导致血浆20α-二氢孕酮浓度升高> 2倍。在该动物模型中，在黄体和非黄体卵巢组织中都检测到糖皮质激素受体蛋白（约92 kDa）。糖皮质激素的这些作用和糖皮质激素受体的存在提高了糖皮质激素在大鼠黄体中的生理作用的可能性。
We investigated the physiological basis for the trophic effect of glucocorticoids in rat corpora lutea in the absence of pituitary gonadotropins. Immature (Day 29) Sprague-Dawley rats were given eCG and hCG to induce the development of corpora lutea and were hypophysectomized on Day 32. Beginning on Day 40, rats received twice-daily s.c. injections of either dexamethasone (dex; 200 μg/rat/day) or vehicle (controls) and then were killed on Day 44. Plasma 20α-dihydroprogesterone, a major steroid produced by the corpora lutea, was higher (p≤ 0.01) in dex-treated than in control rats (44.5 ± 2.3 vs. 23.0 ± 5.6 ng/ml). Dexamethasone treatment increased lipid droplets and lipid in the corpora lutea as revealed by electron microscopy and oil red O staining. Cholesterol esters were higher in corpora lutea of dex-treated rats compared to controls (14.8 ± 1.1 vs. 2.2 ± 0.5 μg/mg corpora lutea wet tissue, respectively;p≤ 0.05). Another group of hypophysectomized rats was treated with either a high or a lower dosage of corticosterone, both of which caused an elevation to > 2-fold of plasma 20α-dihydroprogesterone concentration compared to controls. Glucocorticoid receptor protein (about 92 kDa) was detected in both luteal and nonluteal ovarian tissues in this animal model. These effects of glucocorticoids and the presence of the glucocorticoid receptor raise the possibility of a physiological role for glucocorticoids in the rat corpus luteum.