Ou C W, Chen Z Q, Qi S, Lye S J
Program in Development and Fetal Health, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
Am J Obstet Gynecol. 2000 Apr;182(4):919-25. doi: 10.1016/s0002-9378(00)70347-4.
We examined expression of messenger ribonucleic acid encoding the prostaglandin F(2alpha) receptor in the rat myometrium throughout late gestation and its regulation by progesterone and mechanical stretch.
Normal pregnant rats were killed on gestational day 15, 22, or 23 (during labor) or 1 day post partum. The effects of progesterone on prostaglandin F(2alpha) receptor messenger ribonucleic acid levels were investigated by daily injections of progesterone (4 mg) from day 20 of normal gestation or from day 17 in rats bilaterally ovariectomized on day 17. To investigate the effects of myometrial stretch, unilaterally pregnant rats underwent either sham surgery or placement of a polyvinyl tube 3 mm in diameter in the nongravid uterine horn on day 15 or 18 and were killed 5 days later. Prostaglandin F(2alpha) receptor messenger ribonucleic acid levels in the myometrium were determined by a semiquantitative reverse transcription-polymerase chain reaction method.
Myometrial prostaglandin F(2alpha) receptor messenger ribonucleic acid levels significantly increased during both term and ovariectomy-induced preterm labor. This increase was blocked by progesterone. In rats with unilateral pregnancies prostaglandin F(2alpha) receptor messenger ribonucleic acid levels in the nongravid horns were similar to those in the contralateral gravid horns on day 20 and during labor regardless of whether they were stretched by a 3-mm tube.
Increased myometrial expression of prostaglandin F(2alpha) receptor messenger ribonucleic acid during term and preterm labor is temporally associated with progesterone withdrawal but is not dependent on mechanical stretch of the myometrium.
我们研究了整个妊娠晚期大鼠子宫肌层中编码前列腺素F（2α）受体的信使核糖核酸的表达及其受孕酮和机械牵张的调节。
正常妊娠大鼠在妊娠第15、22或23天（分娩时）或产后1天处死。通过从正常妊娠第20天开始或在第17天双侧卵巢切除的大鼠中从第17天开始每日注射孕酮（4毫克），研究孕酮对前列腺素F（2α）受体信使核糖核酸水平的影响。为了研究子宫肌层牵张的影响，单侧妊娠大鼠在第15天或第18天接受假手术或在非妊娠子宫角放置直径3毫米的聚乙烯管，并在5天后处死。子宫肌层中前列腺素F（2α）受体信使核糖核酸水平通过半定量逆转录-聚合酶链反应法测定。
足月和卵巢切除诱导的早产期间，子宫肌层前列腺素F（2α）受体信使核糖核酸水平显著增加。这种增加被孕酮阻断。在单侧妊娠的大鼠中，无论是否被3毫米的管子牵张，非妊娠侧子宫角中前列腺素F（2α）受体信使核糖核酸水平在第20天和分娩期间与对侧妊娠子宫角相似。
足月和早产期间子宫肌层前列腺素F（2α）受体信使核糖核酸表达增加与孕酮撤退在时间上相关，但不依赖于子宫肌层的机械牵张。
