Placental system A transporter mRNA is not different in preeclampsia, normal pregnancy, or pregnancies with small-for-gestational-age infants.
OBJECTIVE
System A amino acid transporter activity is reduced in placentas from small-for-gestational-age (SGA) compared to normal pregnancies. We compared the expression of the system A transporters between preeclamptic and control and between small-for-gestational-age and controls pregnancies.


METHODS
We used placental samples from 18 preeclamptic pregnancies matched with 17 normal pregnancies and from 16 SGA pregnancies matched with 15 different normal pregnancies. Using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) we quantified the mRNA for two system A subtype target genes ATA1 and ATA2 as well as beta-actin for normalization.


RESULTS
There was no significant difference of mRNA for ATA1 or ATA2 transporters between preeclamptic and their controls or SGA pregnancies and their controls.


CONCLUSIONS
Despite previous studies reporting reduced activity for system A transporters in small-for-gestational-age pregnancies, we found no difference in steady-state concentrations of the mRNA, of the system A transporters among preeclamptic, SGA, and normal control pregnancies. These results do not exclude differences in actual protein levels or activity of the amino acid transporters, which warrant further study.
Malina
Amanda
A
Magee-Womens Research Institute, Pittsburgh, PA 15213, USA.
Daftary
Ashi
A
Crombleholme
William
W
Markovic
Nina
N
Roberts
James M
JM
D000328:Adult; D000704:Analysis of Variance; D001483:Base Sequence; D016022:Case-Control Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010298:Parity; D010920:Placenta / Q000378:metabolism*; D011225:Pre-Eclampsia / Q000175:diagnosis* / Q000378:metabolism; D011247:Pregnancy; D011256:Pregnancy Outcome; D011266:Pregnancy-Associated Plasma Protein-A / Q000378:metabolism; D011295:Prenatal Care; D011336:Probability; D012333:RNA, Messenger / Q000032:analysis*; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012494:Sampling Studies; D012680:Sensitivity and Specificity
D026901:Membrane Transport Proteins; D012333:RNA, Messenger; D011266:Pregnancy-Associated Plasma Protein-A