Thiede M A, Daifotis A G, Weir E C, Brines M L, Burtis W J, Ikeda K, Dreyer B E, Garfield R E, Broadus A E
Department of Bone Biology and Osteoporosis Research, Merck Sharp & Dohme Research Laboratories, West Point, PA 19486.
Proc Natl Acad Sci U S A. 1990 Sep;87(18):6969-73. doi: 10.1073/pnas.87.18.6969.
The parathyroid hormone (PTH) and parathyroid hormone-related peptide (PTHRP) genes are members of a gene family. Whereas PTH is a classical peptide hormone, mounting evidence suggests that the PTHRP may have predominately local actions. We report here that the PTHRP gene is expressed in rat myometrium, with a major peak in PTHRP mRNA expression occurring in the 48 hr immediately preceding parturition. A similar peak in peptide content was found in tissue extracts by biological and immunological assays, but the PTHRP could not be detected in the peripheral circulation or in uterine vein plasma during late gestation. By in situ hybridization histochemistry, PTHRP mRNA was demonstrated in both the longitudinal and circular layers of smooth muscle but was absent in the endometrium. The rise in myometrial PTHRP mRNA in late gestation was dependent upon intrauterine occupancy; it was greatly reduced or absent in nongravid uterine horns. These findings indicate that the expression of the PTHRP gene in preterm myometrium is under the control of a local stimulus and suggest that the PTHRP may play a paracrine or autocrine role in the uterus during the antepartum period, possibly involving myometrial contractility.
甲状旁腺激素（PTH）和甲状旁腺激素相关肽（PTHRP）基因是一个基因家族的成员。虽然PTH是一种经典的肽类激素，但越来越多的证据表明，PTHRP可能主要具有局部作用。我们在此报告，PTHRP基因在大鼠子宫肌层中表达，在分娩前48小时PTHRP mRNA表达出现一个主要峰值。通过生物学和免疫测定在组织提取物中发现了类似的肽含量峰值，但在妊娠晚期外周循环或子宫静脉血浆中未检测到PTHRP。通过原位杂交组织化学，在平滑肌的纵层和环层中均显示有PTHRP mRNA，但在内膜中未发现。妊娠晚期子宫肌层PTHRP mRNA的升高依赖于子宫内有胎儿；在未妊娠的子宫角中其水平大大降低或不存在。这些发现表明，早产子宫肌层中PTHRP基因的表达受局部刺激的控制，并提示PTHRP可能在产前期间在子宫中发挥旁分泌或自分泌作用，可能涉及子宫肌层收缩。
