绵羊前列腺素F2α受体：类固醇对黄体mRNA稳态水平的影响。

Ovine prostaglandin F2alpha receptor: steroid influence on steady-state levels of luteal mRNA.

作者信息

Hoyer P B, Marion S L, Stine I, Rueda B R, Hamernik D L, Regan J W, Wise M E

机构信息

Department of Physiology, The University of Arizona, Tucson 85724, USA.

出版信息

Endocrine. 1999 Apr;10(2):105-11. doi: 10.1385/ENDO:10:2:105.

DOI:10.1385/ENDO:10:2:105

PMID:10451218

Abstract

Expression of the receptor for prostaglandin F2alpha (PGF2alpha) is decreased in the ovine corpus luteum during regression and increased in early pregnancy. This study was designed to evaluate the influence of progesterone and/or 17beta-estradiol (E2) on this regulation. Circulating progesterone (functional regression) and luteal PGF receptor mRNA decreased (p < 0.05) within 8 h of PGF2alpha-induced luteal regression in midluteal phase (day 10; d 10) ewes; however, internucleosomal DNA fragmentation (structural regression) was not yet increased. Additionally, luteal PGF receptor mRNA and circulating progesterone were greater (p < 0.05) in pregnant than in nonpregnant ewes on d 14, but not on d 12. Twelve hours following injection of d 10 ewes with E2, steady-state levels of mRNA for PGF receptor were decreased (p < 0.05), although circulating progesterone and DNA laddering were unchanged. Conversely, luteal mRNA for PGF receptor was increased (p < 0.05) by E2 treatment in hysterectomized ewes. These results provide evidence that (1) luteal PGF receptor expression parallels circulating progesterone levels during functional regression and in early pregnancy, but (2) expression of PGF receptor can be dissociated from alterations in circulating progesterone by injection with E2. Additionally, decreased PGF receptor expression initiated by E2 is uterine-dependent, whereas the direct luteal effect (hysterectomized ewes) of E2 is a stimulation of PGF receptor expression. These results collectively support the belief that the apparent downregulation of PGF receptor during luteal regression is associated with uterine-derived PGF2alpha and its intracellular effects rather than with alterations in ovarian steroid production.

摘要

在绵羊黄体退化过程中，前列腺素F2α（PGF2α）受体的表达降低，而在妊娠早期则升高。本研究旨在评估孕酮和/或17β-雌二醇（E2）对这种调节的影响。在黄体中期（第10天；d 10）的母羊中，PGF2α诱导黄体退化8小时内，循环孕酮（功能性退化）和黄体PGF受体mRNA水平降低（p<0.05）；然而，核小体间DNA片段化（结构性退化）尚未增加。此外，在第14天，妊娠母羊的黄体PGF受体mRNA和循环孕酮水平高于未妊娠母羊（p<0.05），但在第12天并非如此。给第10天的母羊注射E2 12小时后，PGF受体mRNA的稳态水平降低（p<0.05），尽管循环孕酮和DNA梯带未发生变化。相反，在子宫切除的母羊中，E2处理可使黄体PGF受体mRNA增加（p<0.05）。这些结果表明：（1）在功能性退化和妊娠早期，黄体PGF受体表达与循环孕酮水平平行，但（2）注射E2可使PGF受体表达与循环孕酮的变化相分离。此外，E2引发的PGF受体表达降低依赖于子宫，而E2对黄体的直接作用（子宫切除的母羊）是刺激PGF受体表达。这些结果共同支持了这样一种观点，即黄体退化过程中PGF受体的明显下调与子宫来源的PGF2α及其细胞内效应有关，而不是与卵巢类固醇生成的改变有关。