VASOPRESSIN EXPRESSION IN CULTURED NEURONS IS STIMULATED BY CYCLIC-AMP
VASOPRESSIN EXPRESSION IN CULTURED NEURONS IS STIMULATED BY CYCLIC-AMP
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DOI：
10.1111/j.1365-2826.1990.tb00652.x
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发表时间：
1990-01-01
影响因子：
3.2
通讯作者：
SCHMALE, H
中科院分区：
文献类型：
--
作者：
OEDING, P;SCHILLING, K;SCHMALE, H
加压素和催产素基因在下丘脑中相互排斥的大细胞神经元组中表达。 细胞特异性和调节可能由作用于一个或另一个基因的细胞外和细胞内信号控制。 为了确定调节肽表达的因子，我们使用了来自 14 天龄胎鼠的原代分离培养物。 通过联合免疫细胞化学和原位杂交监测加压素表达。 用毛喉素和/或磷酸二酯酶抑制剂 3-异丁基-1-甲基黄嘌呤 (IBMX) 处理培养物（两者都会导致细胞内环 AMP 水平升高），使表达加压素的细胞数量增加多达 10 倍。 通过核糖核酸酶保护测定定量验证特定的加压素信使核糖核酸积累。 Forskolin 和 IBMX 不会改变一般神经元标记物、神经元特异性烯醇化酶和突触素的水平，表明这些药物的作用对表达加压素的细胞具有特异性。 这些药物对大细胞神经元没有促有丝分裂作用。 此外，它们的作用不是跨突触介导的，因为这些药物在低 Ca2+/高 Mg2+ 培养基中生长的培养物以及用破伤风毒素或河豚毒素处理的培养物中也有效。 迄今为止测序的所有加压素基因的 5' 启动子区域中存在转录因子 AP-2 的假定反应元件，这可能为观察到的环 AMP 效应提供分子基础。 催产素基因中不存在此类元件，在我们的培养物中，催产素的信使核糖核酸水平未受到毛喉素和 IBMX 的显着影响。
Vasopressin and oxytocin genes are expressed in mutually exclusive sets of magnocellular neurons in the hypothalamus. Cell specificity and regulation are probably controlled by extra- and intracellular signals acting on one or the other gene. In order to identify factors that regulate peptide expression, we have used primary dissociated cultures derived from 14-day old foetal rats. Vasopressin expression was monitored by combined immunocytochemistry and in situ hybridization. Treatment of cultures with forskolin and/or the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX), both of which result in elevated intracellular cyclic AMP levels, increased the numbers of vasopressin-expressing cells up to 10-fold. The specific vasopressin messenger ribonucleic acid accumulation was verified quantitatively by ribonuclease protection assays. Forskolin and IBMX did not change the levels of the general neuronal markers, neuron-specific enolase and synaptophysin, suggesting that the effect of these drugs was specific for vasopressin-expressing cells. The drugs were not mitogenic for magnocellular neurons. Furthermore, their effect was not mediated trans-synaptically, as the drugs were also effective in cultures grown in low Ca2+/high Mg2+ medium, as well as in cultures treated with either tetanus toxin or tetrodotoxin. The presence of putative response elements for the transcription factor AP-2 in the 5' promotor regions of all vasopressin genes sequenced so far may provide the molecular basis of the observed cyclic AMP effect. No such elements are present in the genes for oxytocin, the messenger ribonucleic acid levels of which were not measurably affected by forskolin and IBMX in our cultures.