Bolton L M, Thomas T H, Macphail S, Dunlop W
Department of Obstetrics, University of Newcastle upon Tyne, United Kingdom.
Am J Obstet Gynecol. 1994 Feb;170(2):693-8. doi: 10.1016/s0002-9378(94)70250-0.
Our purpose was to describe the alterations in erythrocyte sodium pump kinetics and sodium content occurring during the puerperium.
Twelve healthy primigravid women were studied serially from late pregnancy until 20 weeks after delivery. Erythrocyte sodium pump rate constant, maximum velocity, and sodium affinity were calculated from the ouabain-sensitive sodium flux measured in whole blood and in erythrocytes in which sodium content had been altered with the ionophore nystatin. The Student t test was used to compare the regression coefficients of the values plotted against log time for specific periods.
The sodium pump rate constant, maximum velocity, and sodium affinity were lower 20 weeks after delivery than in late pregnancy (0.339 +/- 0.018 vs 0.399 +/- 0.016/hr, 7.02 +/- 0.08 vs 9.98 +/- 0.078 mmol/kg/hr, 2.65 +/- 0.21 vs 3.16 +/- 0.20 mmol/kg). The decrease in the rate constant commenced after 4 days of the puerperium, whereas the decrease in maximum velocity and Michaelis-Menten constant did not commence until after 2 weeks. Erythrocyte sodium content was greater 20 weeks after delivery than in late pregnancy (4.71 +/- 0.20 vs 4.14 +/- 0.15 mmol/kg cells) and the increase was gradual over the time studied.
After delivery the rate constant of the sodium pump measured in plasma and the erythrocyte sodium content changed before any significant alteration in the maximum velocity of the pump. The return of sodium pump function to the nonpregnant state continues beyond 6 weeks after delivery.
我们的目的是描述产褥期红细胞钠泵动力学及钠含量的变化。
对12名健康初产妇进行连续研究，从妊娠晚期直至产后20周。通过测量全血及用离子载体制霉菌素改变钠含量后的红细胞中哇巴因敏感的钠通量，计算红细胞钠泵速率常数、最大速度和钠亲和力。采用Student t检验比较特定时间段内相对于对数时间绘制的值的回归系数。
产后20周时，钠泵速率常数、最大速度和钠亲和力低于妊娠晚期（分别为0.339±0.018对0.399±0.016/小时，7.02±0.08对9.98±0.078毫摩尔/千克/小时，2.65±0.21对3.16±0.20毫摩尔/千克）。速率常数在产后4天开始下降，而最大速度和米氏常数直到2周后才开始下降。产后20周时红细胞钠含量高于妊娠晚期（4.71±0.20对4.14±0.15毫摩尔/千克细胞），且在所研究的时间段内逐渐增加。
产后，血浆中测量的钠泵速率常数和红细胞钠含量在泵的最大速度发生任何显著变化之前就已改变。钠泵功能恢复到非妊娠状态在产后6周后仍在继续。
