Hubel C A, Shakir Y, Gallaher M J, McLaughlin M K, Roberts J M
Magee-Womens Research Institute, Pittsburgh, PA 15213, USA. hubelc+@pitt.edu
J Soc Gynecol Investig. 1998 Sep-Oct;5(5):244-50. doi: 10.1016/s1071-5576(98)00022-7.
To characterize the changes in low-density lipoprotein (LDL) peak particle diameter (diameter of the predominant LDL subclass) in relation to changes in serum triglyceride concentration during successive stages of normal gestation and postpartum.
Nonfasting venous blood was obtained longitudinally during and after uncomplicated primiparous pregnancy from 10 nonsmoking women with no history of metabolic disorders. Plasma LDL diameter was determined by nondenaturing polyacrylamide gel electrophoresis. Serum concentrations of total cholesterol, triglyceride, apolipoprotein B, apolipoprotein A-I, and LDL-cholesterol were measured. Gestational changes were analyzed by one-way repeated-measures analysis of variance and the paired multiple comparison Student-Newman-Keuls test. Pearson coefficients were computed for correlation of serum lipids and LDL diameter.
Low-density lipoprotein diameter decreased progressively with advancing gestation, evident by 16-20 weeks relative to 5-12 weeks. Seven of 10 cases were subclass pattern B (diameter less than 255 A) by term, indicating that small, dense particles predominated. The average diameter decrease from early to late gestation was 13 A. All subjects reverted to subclass pattern A (diameter 255 A or more) by 6-12 weeks postpartum, indicating prevalence of large, buoyant LDL. Low-density lipoprotein diameter correlated inversely with concentrations of serum triglyceride (r = -.61, P < .0001), apo B (r = -.66, P < .0001), cholesterol (r = -.53, P < .001), LDL cholesterol (r = -.45, P < .005), and apo A-I (r = -.39, P < .02).
Gestational triglyceride increases are accompanied by progressive decreases in LDL diameter in a majority of cases. These changes undergo reversal postpartum and therefore are transient. Small, dense LDL particles have a number of properties capable of altering vascular function. However, the consequences of the gestational LDL size decrease for maternal and fetal metabolism remain unknown.
描述正常妊娠及产后各阶段低密度脂蛋白(LDL)峰值颗粒直径(主要LDL亚类的直径)相对于血清甘油三酯浓度变化的情况。
从10名无代谢紊乱病史的非吸烟初产妇在妊娠期间及产后纵向采集非空腹静脉血。通过非变性聚丙烯酰胺凝胶电泳测定血浆LDL直径。测量血清总胆固醇、甘油三酯、载脂蛋白B、载脂蛋白A-I和LDL胆固醇的浓度。采用单向重复测量方差分析和配对多重比较Student-Newman-Keuls检验分析妊娠变化。计算血清脂质与LDL直径的Pearson系数。
随着妊娠进展,低密度脂蛋白直径逐渐减小,相对于孕5 - 12周,在孕16 - 20周时明显可见。10例中有7例在足月时为B亚类模式(直径小于255 Å),表明小而密的颗粒占主导。从妊娠早期到晚期,平均直径减小了13 Å。所有受试者在产后6 - 12周恢复为A亚类模式(直径255 Å或更大),表明大而轻的LDL占优势。低密度脂蛋白直径与血清甘油三酯浓度(r = -0.61,P < 0.0001)、载脂蛋白B(r = -0.66,P < 0.0001)、胆固醇(r = -0.53,P < 0.001)、LDL胆固醇(r = -0.45,P < 0.005)和载脂蛋白A-I(r = -0.39,P < 0.02)呈负相关。
在大多数情况下,妊娠期间甘油三酯升高伴随着LDL直径逐渐减小。这些变化在产后会逆转,因此是短暂的。小而密的LDL颗粒具有许多能够改变血管功能的特性。然而,妊娠期间LDL大小减小对母婴代谢的影响尚不清楚。