Trend S G, Bruce N W
Department of Anatomy and Human Biology, University of Western Australia, Nedlands.
Am J Obstet Gynecol. 1989 Feb;160(2):498-501. doi: 10.1016/0002-9378(89)90480-8.
This study examined the effects of a chronic maternal infusion of epinephrine on development of the rat embryo. Epinephrine was infused during days 1 to 8, 8 to 15, or 15 to 22 of pregnancy to cover periods of implantation, embryogenesis, and rapid fetal growth, respectively. Infusions were accomplished with osmotic minipumps to avoid repeated handling stress. The infusion rate of 0.125 micrograms/min elevated resting plasma concentrations of epinephrine in nonpregnant rats by about sevenfold (from 0.28 to 1.98 ng/ml). Under these conditions, epinephrine did not affect the number of rats maintaining pregnancy, their litter size, or the numbers of resorptions, fetal deaths, and malformations. Fetal and placental weights were unaffected except for a slight trend for fetal weight to be depressed in larger litters of rats treated during days 15 to 22. It seems that the rat embryo is resistant to elevations of epinephrine concentrations equivalent to those observed under mild to severe stress conditions.
本研究考察了母体长期输注肾上腺素对大鼠胚胎发育的影响。在妊娠第1至8天、第8至15天或第15至22天分别输注肾上腺素，以分别覆盖着床期、胚胎形成期和胎儿快速生长期。采用渗透微型泵进行输注，以避免反复处理应激。0.125微克/分钟的输注速率使未怀孕大鼠的静息血浆肾上腺素浓度升高约7倍（从0.28纳克/毫升升至1.98纳克/毫升）。在这些条件下，肾上腺素不影响维持妊娠的大鼠数量、窝仔数，也不影响吸收、胎儿死亡和畸形的数量。除了在第15至22天接受治疗的大鼠较大窝仔中胎儿体重有轻微下降趋势外，胎儿和胎盘重量未受影响。看来大鼠胚胎对相当于在轻度至重度应激条件下观察到的肾上腺素浓度升高具有抗性。
