Stek A M, Fisher B K, Baker R S, Lang U, Tseng C Y, Clark K E
Department of Obstetrics and Gynecology, University of Cincinnati College of Medicine, OH 45267-0526.
Am J Obstet Gynecol. 1993 Oct;169(4):888-97. doi: 10.1016/0002-9378(93)90022-b.
Our purpose was to evaluate the maternal and fetal cardiovascular effects of maternally administered methamphetamine and to determine the extent of placental transfer.
Seven near-term pregnant sheep were surgically instrumented to measure maternal and fetal blood pressure and heart rate, cardiac output, uterine flow, and umbilical flow. A single dose of methamphetamine 1 mg/kg was administered as a bolus to study maternal and fetal cardiovascular responses and placental transfer.
Maternal administration of methamphetamine caused increases in maternal blood pressure, heart rate, cardiac output, and systemic vascular resistance and decreased uterine blood flow. Peak maternal changes occurred within 10 minutes after methamphetamine administration and were near baseline by 180 minutes. Fetal blood pressure increased and returned slowly to baseline by 2 hours. After an initial decrease fetal heart rate increased above baseline values over the next 2 hours. Umbilical blood flow also decreased initially and then increased slightly. Fetal pH and PO2 tended to decrease. Maternal and fetal methamphetamine levels reached a maximum of 2.9 and 1.9 micrograms/ml, respectively. Rapid and significant placental transfer, delayed excretion into the amniotic fluid, and slow elimination from the maternal and fetal circulation were demonstrated.
Methamphetamine readily crosses the ovine placenta, producing significant and long-lasting maternal and fetal cardiovascular effects, which may have long-term consequences, especially if administered repetitively.
我们的目的是评估母体使用甲基苯丙胺对母体和胎儿心血管系统的影响，并确定胎盘转运的程度。
对7只近足月妊娠绵羊进行手术植入监测仪器，以测量母体和胎儿的血压、心率、心输出量、子宫血流量和脐血流量。静脉推注1 mg/kg单剂量甲基苯丙胺，以研究母体和胎儿的心血管反应以及胎盘转运情况。
母体使用甲基苯丙胺导致母体血压、心率、心输出量和全身血管阻力增加，子宫血流量减少。甲基苯丙胺给药后10分钟内母体变化达到峰值，180分钟时接近基线水平。胎儿血压升高，并在2小时内缓慢恢复至基线。在最初下降后，胎儿心率在接下来的2小时内升至基线值以上。脐血流量最初也减少，然后略有增加。胎儿pH值和PO2趋于下降。母体和胎儿甲基苯丙胺水平分别最高达到2.9微克/毫升和1.9微克/毫升。研究表明甲基苯丙胺可快速且显著地通过胎盘转运，排泄至羊水的过程延迟，且从母体和胎儿循环中清除缓慢。
甲基苯丙胺可轻易穿过绵羊胎盘，对母体和胎儿心血管系统产生显著且持久的影响，这可能会产生长期后果，尤其是反复使用时。
