Dynamic changes in luteinizing hormone releasing hormone transcriptional activity are associated with the steroid-induced LH surge.
Dynamic changes in luteinizing hormone releasing hormone transcriptional activity are associated with the steroid-induced LH surge.
复制标题
黄体生成素释放激素转录活性的动态变化与类固醇诱导的 LH 激增有关。
DOI：
10.1016/s0006-8993(01)03151-1
复制
发表时间：
2001
期刊：
影响因子：
2.9
通讯作者：
Rubin,BS
中科院分区：
文献类型：
--
作者：
Jimenez-Linan,M;Rubin,BS
用RNA酶保护试验检测了去卵巢雌性大鼠在激素诱导的LH峰当天的促黄体生成素释放激素（LHRH）基因转录。LHRH mRNA水平在胞质提取物中进行测量，LHRH初级转录水平在从包含终板血管器（OVLT）和视前区（POA）的组织碎片制备的核提取物中进行测量。成熟和初级转录物水平的测量显示出随时间的适度但显著的变化。LHRH初级转录水平的变化之前的成熟mRNA水平的变化表明在这个时候的LHRH mRNA的细胞质池的基因转录的变化的可检测的响应延迟。当与循环LH滴度相关时，LHRH初级转录水平在LH峰开始之前和LH峰达到峰值水平之后较高，并且在LH峰的上升阶段期间下降。这些研究结果表明，LHRH基因转录增加的潜在作用，在LHRH的积累开始之前的LH激增，并在补充LHRH商店耗尽激增期间。此外，LH峰上升期LHRH基因转录的减少可能对限制峰持续时间很重要。所提出的数据是一致的作用，在调节参数的类固醇诱导的LH峰和补充释放池的这一必要的十肽LHRH转录活性的动态变化。
Luteinizing hormone releasing hormone (LHRH) gene transcription was examined in ovariectomized female rats on the day of a steroid-induced LH surge using the RNase protection assay. LHRH mRNA levels were measured in cytosolic extracts, and LHRH primary transcript levels were measured in nuclear extracts prepared from tissue fragments that contained the organum vasculosum of the lamina terminalis (OVLT) and the preoptic area (POA). Measurements of both mature and primary transcript levels demonstrated modest but significant changes over time. Alterations in LHRH primary transcript levels preceded changes in levels of mature mRNA suggesting a delay in the detectable response of the cytoplasmic pool of LHRH mRNA to changes in gene transcription at this time. When viewed in relation to circulating LH titers, LHRH primary transcript levels were high prior to the start of the LH surge and after peak levels of LH were attained, and they declined during the ascending phase of the LH surge. These findings suggest a potential role for increased LHRH gene transcription in the accumulation of LHRH prior to the start of the LH surge and in the replenishment of LHRH stores depleted during the surge. Moreover, the decrease in LHRH gene transcription during the ascending phase of the LH surge may be important for limiting surge duration. The data presented are consistent with a role for dynamic changes in LHRH transcriptional activity in modulating parameters of the steroid-induced LH surge and in replenishing the releasable pool of this essential decapeptide.