Kwon Hyukjung, Wu Guoyao, Bazer Fuller W, Spencer Thomas E
Department of Animal Science and Center for Animal Biotechnology and Genomics, Texas A and M University, College Station, Texas 77843-2471, USA.
Biol Reprod. 2003 Nov;69(5):1626-34. doi: 10.1095/biolreprod.103.019067. Epub 2003 Jul 9.
Polyamines (putrescine, spermidine, and spermine) are essential for placental growth and angiogenesis. However, little is known about changes in polyamine synthesis associated with development of the ovine conceptus (embryo/fetus and associated placental membranes). We hypothesized that rates of placental polyamine synthesis were maximal during the rapid placental growth that occurs in the first half of pregnancy. This hypothesis was tested using ewes between Days 30 and 140 of gestation. Columbia cross-bred ewes were hysterectomized on Days 30, 40, 60, 80, 100, 120, or 140 of gestation (Day 0 = mating; n = 4 ewes/day) to obtain placentomes, intercotyledonary placenta, intercaruncular endometrium, and allantoic as well as amniotic fluids. The tissues were analyzed for ornithine decarboxylase (ODC) and arginase activities; arginine, ornithine, and polyamine concentrations; and polyamine synthesis using radiochemical and chromatographic methods. Maximal ODC and arginase activities and the highest rates of polyamine synthesis were observed in all tissues on Day 40 of gestation. Concentrations of ornithine and polyamines in placentomes and intercaruncular endometrium also peaked on Day 40 of gestation. In ovine allantoic and amniotic fluids, polyamines were most abundant during early (Days 40-60) and late (Days 100-140) gestation, respectively. Amniotic fluid spermine increased progressively with advancing gestation. Results of the present study indicate metabolic coordination among the several integrated pathways that support high rates of polyamine synthesis in the placenta and endometrium during early pregnancy. Our findings may have important implications for both intrauterine growth retardation and fetal origins of diseases in adults.
多胺（腐胺、亚精胺和精胺）对胎盘生长和血管生成至关重要。然而，关于绵羊孕体（胚胎/胎儿及相关胎盘膜）发育过程中多胺合成的变化却知之甚少。我们推测，胎盘多胺合成速率在妊娠前半期胎盘快速生长期间达到最大值。使用妊娠第30天至140天的母羊对这一假设进行了验证。在妊娠第30、40、60、80、100、120或140天（第0天 = 交配；每天n = 4只母羊）对哥伦比亚杂交母羊进行子宫切除，以获取胎盘小叶、叶间胎盘、肉阜间子宫内膜、尿囊液和羊水。采用放射化学和色谱方法分析组织中的鸟氨酸脱羧酶（ODC）和精氨酸酶活性、精氨酸、鸟氨酸和多胺浓度以及多胺合成情况。在妊娠第40天，所有组织均观察到最大的ODC和精氨酸酶活性以及最高的多胺合成速率。胎盘小叶和肉阜间子宫内膜中的鸟氨酸和多胺浓度也在妊娠第40天达到峰值。在绵羊尿囊液和羊水中，多胺分别在妊娠早期（第40 - 60天）和晚期（第100 - 140天）最为丰富。羊水中的精胺随着妊娠进展而逐渐增加。本研究结果表明，在妊娠早期，支持胎盘和子宫内膜中多胺合成高速率的几种整合途径之间存在代谢协调。我们的发现可能对宫内生长迟缓以及成人疾病的胎儿起源都具有重要意义。
