Glazier J D, Cetin I, Perugino G, Ronzoni S, Grey A M, Mahendran D, Marconi A M, Pardi G, Sibley C P
Department of Child Health, University of Manchester, St. Mary's Hospital, United Kingdom.
Pediatr Res. 1997 Oct;42(4):514-9. doi: 10.1203/00006450-199710000-00016.
Primarily, our objectives were to compare system A amino acid transporter activity in the microvillous plasma membrane (MVM) of placentas from normally grown (appropriate for gestational age, AGA) and intrauterine growth-restricted (IUGR) fetuses delivered during the third trimester, as a whole and in relation to the severity of IUGR. Ten AGA and 16 IUGR pregnancies were studied at the time of elective cesarean section performed between 28 and 40 wk of gestation. Severity of IUGR pregnancies was assessed primarily by Doppler velocimetry and fetal heart rate monitoring. Placental MVM vesicles were prepared, and system A activity in these was measured. The transporter activity was significantly lower in IUGR compared with AGA pregnancies. Within the IUGR group system A activity was only significantly lower, compared with AGA, in cases that presented with a reduction in umbilical blood flow. We conclude that placental MVM system A activity is lower in IUGR compared with AGA pregnancies delivered during the third trimester. System A activity is related to the severity of IUGR.
主要地，我们的目标是比较来自孕晚期出生的正常生长（适于胎龄，AGA）胎儿和宫内生长受限（IUGR）胎儿胎盘微绒毛质膜（MVM）中系统A氨基酸转运体的活性，整体比较以及与IUGR的严重程度相关的比较。在妊娠28至40周之间进行择期剖宫产时，研究了10例AGA妊娠和16例IUGR妊娠。IUGR妊娠的严重程度主要通过多普勒测速法和胎儿心率监测进行评估。制备胎盘MVM囊泡，并测量其中的系统A活性。与AGA妊娠相比，IUGR中的转运体活性显著降低。在IUGR组中，仅在脐血流减少的病例中，系统A活性与AGA相比才显著降低。我们得出结论，与孕晚期出生的AGA妊娠相比，IUGR中胎盘MVM系统A活性较低。系统A活性与IUGR的严重程度相关。
