Thomsen J K, Fogh-Andersen N, Jaszczak P
Department of Obstetrics and Gynecology, Herlev Hospital, Copenhagen, Denmark.
Acta Obstet Gynecol Scand. 1994 Jan;73(1):14-20. doi: 10.3109/00016349409013386.
The reports on plasma concentrations and physiological function of atrial natriuretic peptide (ANP) during pregnancy are conflicting. In a recent prospective study, including 40 healthy primigravidae, we found a highly significant decrease in the plasma concentration of ANP (p-ANP) during the third trimester and the results indicated that ANP takes part in regulation of blood volume and renal function during pregnancy as in the nonpregnant state. In order to test these results, a study was performed in primigravidae with twin pregnancy to test if the accentuated physiological changes here were followed by a corresponding greater decrease in p-ANP.
Ten healthy primigravidae with twin pregnancy were examined four times during pregnancy plus 12 weeks after delivery. Each time the following were measured: p-ANP, aldosterone, renin, blood volume (carbon monoxide), cardiac output (Doppler), blood pressure and sodium excretion. Interdependence of the changes in ANP and in the other parameters was tested using Spearman's rank correlation test on the delta (delta)-values (the differences in measurements between investigations). The results were compared to the results obtained during singleton pregnancy using the Mann-Whitney rank sum test.
All pregnant values of p-ANP during twin pregnancy were lower than 12 weeks after delivery, p < 0.01. In the 20th, 28th, and 32nd week p-ANP was lower in twin pregnancy than in singleton pregnancy, p < 0.05. There was a negative correlation between changes in p-ANP and changes in: a) blood volume, R = -0.8, p < 0.0001, b) aldosterone, R = -0.66, p < 0.0001, c) renin, R = -0.52, p < 0.01, d) cardiac output, R = -0.68, p < 0.0001. There was a positive correlation between changes in p-ANP and changes in: a) fractional excretion of sodium, R = 0.73, p < 0.0001, and b) total peripheral resistance, R = 0.61, p < 0.0001.
The results suggest that the competitive relationship between ANP and the renin-aldosterone system in regulating sodium balance and fluid volume is preserved during pregnancy. The vasodilation during pregnancy is not mediated by ANP.
关于孕期心房利钠肽（ANP）的血浆浓度及生理功能的报道相互矛盾。在最近一项纳入40名健康初产妇的前瞻性研究中，我们发现孕晚期ANP（p-ANP）的血浆浓度显著降低，结果表明，与非孕期状态一样，ANP参与孕期血容量和肾功能的调节。为验证这些结果，我们对怀有双胎的初产妇进行了一项研究，以检测此处更为明显的生理变化是否伴随着p-ANP相应更大幅度的降低。
对10名怀有双胎的健康初产妇在孕期进行4次检查，并在产后12周进行一次检查。每次均测量以下指标：p-ANP、醛固酮、肾素、血容量（一氧化碳）、心输出量（多普勒）、血压和钠排泄量。使用Spearman秩相关检验对差值（δ值，即各次检查之间测量值的差异）进行分析，以检测ANP变化与其他参数变化之间的相关性。使用Mann-Whitney秩和检验将结果与单胎妊娠时获得的结果进行比较。
双胎妊娠期间p-ANP的所有孕期测量值均低于产后12周，p<0.01。在孕20周、28周和32周时，双胎妊娠的p-ANP低于单胎妊娠，p<0.05。p-ANP变化与以下指标变化之间存在负相关：a）血容量，R = -0.8，p<0.0001；b）醛固酮，R = -0.66，p<0.0001；c）肾素，R = -0.52，p<0.01；d）心输出量，R = -0.68，p<0.0001。p-ANP变化与以下指标变化之间存在正相关：a）钠排泄分数，R = 0.73，p<0.0001；b）总外周阻力，R = 0.61，p<0.0001。
结果表明，孕期ANP与肾素-醛固酮系统在调节钠平衡和液体容量方面的竞争关系得以维持。孕期的血管舒张并非由ANP介导。
