Miller B G
Aust J Biol Sci. 1978 Dec;31(6):641-8. doi: 10.1071/bi9780641.
The effects of ovariectomy and treatment with progesterone and oestradiol on foetal and placental growth were examined. The occurrence of cellular hypertrophy and hyperplasia in the placenta in response to treatments was determined by measuring protein, DNA and RNA:DNA ratios. In control mice, which had not been ovariectomized, the daily administration of 0.01-2.56 microgram oestradiol on days 10-15 of pregnancy caused only small decreases in the number of live foetuses and foetal and placental weights on day 16. When mice were ovariectomized on day 10, gestation was maintained by administering 5 mg progesterone daily, but terminated when only 1 mg progesterone was given daily. However, when ovariectomized mice receiving 1 mg progesterone were also given 0.01 microgram oestradiol on days 10-15, gestation was maintained and the number of live foetuses and foetal and placental weights on day 16 were normal. Increasing the daily dose of oestradiol up to 2.56 microgram in mice receiving 1 mg progesterone on days 10-15 had no effect on foetal and placental growth. In contrast, the daily administration of 0.64-2.56 microgram oestradiol to ovariectomized mice receiving 5 mg progesterone on days 10-15 terminated gestation in some mice and considerably reduced the number of live foetuses and foetal and placental weights in those mice which remained pregnant on day 16. None of the treatments increased protein DNA or the RNA:DNA ratio in the placenta to levels above those seen in control mice. The results are discussed in relation to ovariectomy-induced placental overgrowth in the rat.
研究了卵巢切除以及用孕酮和雌二醇治疗对胎儿及胎盘生长的影响。通过测量蛋白质、DNA以及RNA:DNA比率，确定胎盘因这些治疗而发生细胞肥大和增生的情况。在未进行卵巢切除的对照小鼠中，于妊娠第10至15天每日给予0.01 - 2.56微克雌二醇，仅使第16天的活胎数量、胎儿及胎盘重量略有下降。在第10天进行卵巢切除的小鼠，通过每日给予5毫克孕酮维持妊娠，但每日仅给予1毫克孕酮时妊娠终止。然而，在第10至15天接受1毫克孕酮的卵巢切除小鼠同时给予0.01微克雌二醇时，妊娠得以维持，且第16天的活胎数量、胎儿及胎盘重量均正常。在第10至15天接受1毫克孕酮的小鼠中，将雌二醇的每日剂量增至2.56微克，对胎儿及胎盘生长无影响。相比之下，在第10至15天接受5毫克孕酮的卵巢切除小鼠中，每日给予0.64 - 2.56微克雌二醇，在一些小鼠中导致妊娠终止，并且在第16天仍保持妊娠的小鼠中，活胎数量、胎儿及胎盘重量显著降低。所有处理均未使胎盘的蛋白质DNA或RNA:DNA比率升高至高于对照小鼠的水平。结合大鼠卵巢切除诱导的胎盘过度生长对结果进行了讨论。
