Allen J, Maigaard S, Christensen J H, Andreasen F, Forman A
Department of Obstetrics and Gynecology, Aarhus Kommunehospital, Denmark.
Br J Anaesth. 1987 Oct;59(10):1273-7. doi: 10.1093/bja/59.10.1273.
Small placental stem villous arteries were micro dissected from specimens obtained at normal term vaginal delivery (n = 25). Ring preparations of the vessels were mounted in organ baths and isometric tension was measured. Prostaglandin F2 alpha (PGF2 alpha) 10(-7)-10(-4) mol litre-1 produced concentration-dependent contractile responses that were inhibited by thiopentone 10(-4)-10(-3) mol litre-1 and by chlormethiazole 3 x 10(-4)-3 x 10(-3) mol litre-1. Thiopentone 10(-4)-10(-3) mol litre-1 and chlormethiazole 3 x 10(-4)-3 x 10(-3) mol litre-1 decreased the tension in vessels previously treated with PGF2 alpha 10(-5) mol litre-1. Chlormethiazole 3 x 10(-3) mol litre-1 inhibited, and thiopentone 10(-4)-10(-3) mol litre-1 abolished contractile responses to 5-hydroxytryptamine. Contractions induced by angiotensin II were inhibited by thiopentone 10(-3) mol litre-1 and chlormethiazole 3 x 10(-3) mol litre-1. The concentrations of the two drugs needed to affect contractile activation of isolated human stem villous arteries exceeded the free plasma concentrations reached during anaesthesia induced by the agents during Caesarean section, and the present results do not suggest any major effects of thiopentone or chlormethiazole on fetal placental vascular resistance during the clinical use of these drugs.
从足月阴道分娩获取的标本（n = 25）中显微解剖出小的胎盘绒毛干动脉。将血管环标本安装在器官浴槽中并测量等长张力。前列腺素F2α（PGF2α）10(-7)-10(-4) mol/L产生浓度依赖性收缩反应，该反应被10(-4)-10(-3) mol/L的硫喷妥钠和3×10(-4)-3×10(-3) mol/L的氯美噻唑抑制。10(-4)-10(-3) mol/L的硫喷妥钠和3×10(-4)-3×10(-3) mol/L的氯美噻唑降低了先前用10(-5) mol/L PGF2α处理过的血管中的张力。3×10(-3) mol/L的氯美噻唑抑制，而10(-4)-10(-3) mol/L的硫喷妥钠消除对5-羟色胺的收缩反应。10(-3) mol/L的硫喷妥钠和3×10(-3) mol/L的氯美噻唑抑制血管紧张素II诱导的收缩。影响离体人胎盘绒毛干动脉收缩激活所需的这两种药物的浓度超过了剖宫产时这些药物诱导麻醉期间达到的游离血浆浓度，目前的结果并不表明硫喷妥钠或氯美噻唑在这些药物临床使用期间对胎儿胎盘血管阻力有任何主要影响。
