van de Walle A F, Martin C B
Eur J Obstet Gynecol Reprod Biol. 1987 May;25(1):67-75. doi: 10.1016/0028-2243(87)90093-1.
Cardiac output and its distribution were measured using the microsphere technique before and at 2 and 6 h during the infusion of ritodrine, 1.5 microgram X min-1 X kg-1 i.v., into near-term pregnant guinea pigs. Average cardiac output increased 16 and 25%, and total peripheral resistance decreased 16 and 19% after 2 and 6 h of ritodrine infusion. The carcass and gastrointestinal tract together received two-thirds of the extra cardiac output. Uteroplacental blood flow and uteroplacental vascular resistance were not significantly different from the preinfusion values after 2 h of ritodrine treatment, but were increased 35% and decreased 31%, respectively (p less than 0.05 and less than 0.01), after 6 h of infusion. The increase in uteroplacental blood flow between the 2- and 6-h measurements was positively, and the decrease in uteroplacental vascular resistance negatively correlated with the increase in cardiac output during the same period.
采用微球技术，在向近足月妊娠豚鼠静脉输注利托君（1.5微克·分钟⁻¹·千克⁻¹）之前、输注期间2小时和6小时时，测量心输出量及其分布。输注利托君2小时和6小时后，平均心输出量分别增加了16%和25%，总外周阻力分别降低了16%和19%。躯体和胃肠道共接受了额外心输出量的三分之二。利托君治疗2小时后，子宫胎盘血流量和子宫胎盘血管阻力与输注前值相比无显著差异，但输注6小时后，子宫胎盘血流量分别增加了35%，子宫胎盘血管阻力降低了31%（P＜0.05和＜0.01）。在2小时和6小时测量之间，子宫胎盘血流量的增加与同期心输出量的增加呈正相关，子宫胎盘血管阻力的降低与同期心输出量的增加呈负相关。
