Miyake Y, Murata Y, Hesser J, Tyner J
Department of Obstetrics and Gynecology, University of California, Irvine, Orange 92668.
J Reprod Med. 1991 Oct;36(10):735-40.
Fetal cardiovascular responses to infused norepinephrine (NE) and arginine vasopressin (AVP) were compared in bilaterally vagotomized and chronically catheterized (control) fetal lambs. In the control fetuses, NE infusion was characterized during the first five minutes by a decreased fetal heart rate (FHR) and increased mean arterial blood pressure (MABP) and by a preejection period (PEP) followed by a gradual return to the original values. NE infusion in vagotomized fetuses was followed by tachycardia, decreased PEP without the initial prolongation and an MABP response similar to that in the controls. AVP in control fetuses caused a persistent decrease in the FHR and increase in MABP and PEP. Vagotomy affected only the FHR response: the decrease was persistent but smaller. AVP produced persistent fetal cardiovascular responses regardless of vagotomy; however, the biphasic response FHR pattern, suggestive of NE tachyphylaxis, was eliminated by vagotomy.
在双侧迷走神经切断并长期插管（对照）的胎羊中，比较了胎儿心血管系统对输注去甲肾上腺素（NE）和精氨酸加压素（AVP）的反应。在对照胎儿中，输注NE的前五分钟表现为胎儿心率（FHR）下降、平均动脉血压（MABP）升高，射血前期（PEP）延长，随后逐渐恢复到初始值。迷走神经切断的胎儿输注NE后出现心动过速，PEP缩短且无初始延长，MABP反应与对照组相似。对照胎儿输注AVP导致FHR持续下降、MABP和PEP升高。迷走神经切断仅影响FHR反应：下降持续但幅度较小。无论是否进行迷走神经切断，AVP都会产生持续的胎儿心血管反应；然而，提示NE快速耐受性的双相FHR反应模式在迷走神经切断后消失。
