Qi Juan, Liu Yue-hua, Wang Fei, Shao Xiao, Song Wei-hua
Department of Orthodontics, School of Stomatology, Tongji University, Shanghai 200072, China.
Zhonghua Kou Qiang Yi Xue Za Zhi. 2007 Feb;42(2):85-9.
To explore gene expression of estrogen receptor (ERalpha, ERbeta) and androgen receptor (AR) in genioglossal muscle (GG) of adult male rats, and to investigate the effects of sex hormones on GG activities, ERalpha, ERbeta and AR expression.
GG samples were collected from 10 healthy adult male rats. Total RNA were extracted and subjected to fluorescent quantitative reverse transcription-polymerase chain reaction (FQ RT-PCR) for quantitative measurement of ERalpha, ERbeta and AR mRNAs. The other 24 male rats were randomly divided into 3 groups: control group, estrogen group (intramuscular injection of estrogen 0.1 mg/kg, twice a week) and androgen group (intramuscular injection of androgen 2.5 mg/kg, twice a week). The electromyographic activities (EMG) and contract tension of GG were investigated after 4-week treatment. The expression of ERalpha, ERbeta and AR was assessed by Western blot.
The mRNA expression ratios of AR/GAPDH, ERalpha/GAPDH, ERbeta/GAPDH and ERalpha/ERbeta were (295.80 +/- 127.20), (2042.00 +/- 921.57), (65.96 +/- 29.57) and (36.83 +/- 19.66), respectively. The mRNA level of ERalpha was significantly higher than that of ERbeta (P < 0.01). Compared with the control group, the EMG of GG was intensified in the estrogen group (P < 0.01). GG contractility did not change significantly (P > 0.05), and ERalpha expression in GG was up-regulated by estrogen (P < 0.05); while in the androgen group, the EMG of GG was weakened (P < 0.05). P(t) and P(0) were slightly increased (P > 0.05) and the decline rate of P(0) was markedly quickened (P < 0.05). AR and ERbeta expressions were down-regulated by androgen (P < 0.05).
Both AR and ER were expressed in GG of adult male rats, and ERalpha was expressed more abundantly than ERbeta. Estrogen could greatly improve activities of GG and stimulate the expression of ERalpha. Whereas, androgen could restrain activities of GG, impair its fatigue resistance capacity and inhibit the expression of AR and ERbeta.
探讨成年雄性大鼠颏舌肌（GG）中雌激素受体（ERα、ERβ）和雄激素受体（AR）的基因表达情况，并研究性激素对GG活性、ERα、ERβ和AR表达的影响。
从10只健康成年雄性大鼠采集GG样本。提取总RNA，进行荧光定量逆转录-聚合酶链反应（FQ RT-PCR）以定量测定ERα、ERβ和AR的mRNA。将另外24只雄性大鼠随机分为3组：对照组、雌激素组（肌肉注射雌激素0.1mg/kg，每周2次）和雄激素组（肌肉注射雄激素2.5mg/kg，每周2次）。4周治疗后检测GG的肌电图活动（EMG）和收缩张力。通过蛋白质免疫印迹法评估ERα、ERβ和AR的表达。
AR/GAPDH、ERα/GAPDH、ERβ/GAPDH和ERα/ERβ的mRNA表达比值分别为（295.80±127.20）、（2042.00±921.57）、（65.96±29.57）和（36.83±19.66）。ERα的mRNA水平显著高于ERβ（P<0.01）。与对照组相比，雌激素组GG的EMG增强（P<0.01）。GG收缩性无明显变化（P>0.05），雌激素使GG中ERα表达上调（P<0.05）；而雄激素组GG的EMG减弱（P<0.05）。P(t)和P(0)略有增加（P>0.05），P(0)的下降速率明显加快（P<0.05）。雄激素使AR和ERβ表达下调（P<0.05）。
成年雄性大鼠的GG中AR和ER均有表达，且ERα的表达量高于ERβ。雌激素可显著提高GG的活性并刺激ERα的表达。而雄激素可抑制GG的活性，损害其抗疲劳能力，并抑制AR和ERβ的表达。
