Changes in hormone responsiveness of chick oviduct during primary stimulation with estrogen.
Changes in hormone responsiveness of chick oviduct during primary stimulation with estrogen.
复制标题
雌激素初次刺激期间雏鸡输卵管激素反应性的变化。
DOI：
10.1016/0012-1606(80)90346-2
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发表时间：
1980
影响因子：
2.7
通讯作者：
Palmiter,RD
中科院分区：
文献类型：
--
作者：
Moen,RC;Palmiter,RD
通过与互补dna （cDNA）杂交，监测了雌性激素初次刺激雏鸡输卵管时卵白蛋白mRNA （mRNAov）和蛋白蛋白mRNA （mRNAcon）的诱导情况。在未受刺激的输卵管中，每个细胞检测到大约4个和30个mrnav分子，在用苯甲酸雌二醇治疗1天后，这些水平分别增加到约250和300分子/细胞。这两种mrna的积累速率大约比在二次刺激期间观察到的速率低一个数量级，即在先前雌激素治疗后重新刺激的鸟类中。与cdnaov的原位杂交显示，在雌激素治疗的一天内，几乎所有的输卵管上皮细胞都积累了mrnaov，并且应答细胞的百分比与停药的输卵管大致相同；因此，初次刺激时的次极大反应不能用反应细胞数量的差异来解释。体内注射雌激素后3小时内，输卵管内核雌激素受体的数量从850个增加到4500个。这些值大于早期二次刺激时测量到的核受体数量，这意味着核受体不是一次刺激时的限速成分。因此，我们认为受体诱导的转录或mRNA稳定在初次刺激期间是次优的。100 nm17 β-雌二醇培养的输卵管外植体能够诱导mRNAovand mRNAcon。这种诱导发生在DNA合成没有显著变化的情况下，并且不受羟基脲的影响。这些观察结果，连同他们的体内研究，表明雌激素对输卵管的初次刺激在性质上与二次刺激相似，mRNAovand mrnon的初始积累发生在细胞分裂之前。黄体酮和糖皮质激素在初次刺激时都不能诱导mRNAovor mrnaaconin，而在早期二次刺激时，它们与雌激素一样有效。因此，在雌激素的初次刺激期间，输卵管对这些其他类固醇激素产生反应。即使没有持续的雌激素刺激，这种反应性也能保持。雌激素必须存在超过36小时，以允许随后的黄体酮二次刺激。孕激素受体水平在首次雌激素刺激后36至48小时增加数倍；这个时间与黄体酮开始影响mRNA积累和形态发生的时间密切相关。
The induction of ovalbumin mRNA (mRNAov) and conalbumin mRNA (mRNAcon) during primary stimulation of the chick oviduct with estrogen was monitored by hybridization with complementary DNAs (cDNA). Approximately 4 mRNAovand 30 mRNAconmolecules per cell were detected in the unstimulated oviduct and these levels increased to about 250 and 300 molecules/cell, respectively, after 1 day of treatment with estradiol benzoate. The rates of accumulation of both mRNAs were about an order of magnitude lower than the rates observed during secondary stimulation, i.e., in birds withdrawn from prior estrogen treatment and then restimulated.In situhybridization with cDNAovrevealed that nearly all of the epithelial cells of the oviduct accumulate mRNAovwithin a day of estrogen treatment and that the percentage of responsive cells is about the same as in withdrawn oviducts; thus, the submaximal response during primary stimulation cannot be explained by a difference in the number of responsive cells. The number of nuclear estrogen receptors in the oviduct increases from 850 to 4500 molecules per cell within 3 hr of estrogen administrationin vivo. These values are greater than the number of nuclear receptors measured during early secondary stimulation, implying that nuclear receptors are not the rate-limiting component during primary stimulation. Therefore, we propose that receptor-induced transcription or mRNA stabilization is suboptimal during primary stimulation. Oviduct explants incubated in culture with 100 nM17β-estradiol are able to induce mRNAovand mRNAcon. This induction occurs without a significant change in DNA synthesis and is unaffected by hydroxyurea. These observations, taken together with thein vivostudies, indicate that primary stimulation of the oviduct with estrogen is qualitatively similar to secondary stimulation and that the initial accumulation of mRNAovand mRNAconoccurs prior to cell division. Neither progesterone nor glucocorticoids induce mRNAovor mRNAconduring primary stimulation, whereas they are both as effective as estrogen during early secondary stimulation. Thus, during primary stimulation with estrogen, the oviduct becomes responsive to these other steroid hormones. This responsiveness is maintained even in the absence of continued estrogen stimulation. Estrogen must be present for more than 36 hr to allow subsequent secondary stimulation with progesterone. Progesterone receptor levels increase several-fold between 36 and 48 hr after primary stimulation with estrogen; this time correlates well with the time when progesterone begins to show effects on mRNA accumulation and morphogenesis.