Brann D W, Putnam C D, Mahesh V B
Department of Physiology and Endocrinology, Medical College of Georgia, Augusta 30912-3000.
Endocrinology. 1990 Jan;126(1):159-66. doi: 10.1210/endo-126-1-159.
The purpose of this study was to determine if glucocorticoids had any direct effects on the release of gonadotropin. In estrogen-primed ovariectomized immature rats, triamcinolone acetonide and deoxycorticosterone (1 mg/kg BW) caused a surge in both serum LH and FSH levels. Dexamethasone treatment (0.05 mg/kg BW) resulted in a highly significant selective release of FSH. Cortisol (1 mg/kg BW) suppressed serum FSH levels. A systematic dose-response study showed that triamcinolone acetonide significantly released LH and FSH and suppressed PRL at all doses tested (range, 0.25-4 mg/kg BW). Deoxycorticosterone was not as potent as triamcinolone acetonide and only doses greater than 0.8-1 mg/kg BW significantly released LH and FSH. Dexamethasone selectively released FSH at low doses (0.01, 0.02, 0.05, and 0.1 mg/kg BW) and inhibited LH at higher doses (0.5 and 1.0 mg/kg BW). A single low dose of dexamethasone (0.02 mg/kg BW) was found to significantly release LH. With respect to PRL secretion, a biphasic effect of dexamethasone was observed in that the lowest dose (0.01 mg/kg BW) stimulated PRL release while the highest dose (1.0 mg/kg BW) significantly inhibited PRL release. Triamicolone acetonide and deoxycorticosterone were found to require estrogen priming for their effects on gonadotropin secretion. The findings in this study raise the possibility that the beneficial effects seen with corticosteroids in inducing ovulation in polycystic ovarian syndrome may be due, in part, to their direct effects upon the release of gonadotropins.
本研究的目的是确定糖皮质激素对促性腺激素释放是否有任何直接影响。在雌激素预处理的去卵巢未成熟大鼠中，曲安奈德和脱氧皮质酮（1毫克/千克体重）导致血清促黄体生成素（LH）和促卵泡生成素（FSH）水平激增。地塞米松治疗（0.05毫克/千克体重）导致FSH高度显著的选择性释放。皮质醇（1毫克/千克体重）抑制血清FSH水平。一项系统性剂量反应研究表明，在所有测试剂量（范围为0.25 - 4毫克/千克体重）下，曲安奈德均能显著释放LH和FSH并抑制催乳素（PRL）。脱氧皮质酮的效力不如曲安奈德，只有大于0.8 - 1毫克/千克体重的剂量才能显著释放LH和FSH。地塞米松在低剂量（0.01、0.02、0.05和0.1毫克/千克体重）时选择性释放FSH，在高剂量（0.5和1.0毫克/千克体重）时抑制LH。发现单次低剂量地塞米松（0.02毫克/千克体重）能显著释放LH。关于PRL分泌，观察到地塞米松有双相作用，即最低剂量（0.01毫克/千克体重）刺激PRL释放，而最高剂量（1.0毫克/千克体重）显著抑制PRL释放。发现曲安奈德和脱氧皮质酮对促性腺激素分泌的影响需要雌激素预处理。本研究中的发现增加了一种可能性，即皮质类固醇在多囊卵巢综合征诱导排卵中所见的有益作用可能部分归因于它们对促性腺激素释放的直接影响。
