Placental system A transporter mRNA is not different in preeclampsia, normal pregnancy, or pregnancies with small-for-gestational-age infants.

Abstract

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.

• Authors: Amanda Malina, Ashi Daftary, William Crombleholme, Nina Markovic, James M Roberts
• Journal: Hypertension in pregnancy (Hypertens Pregnancy) Vol. 24 Issue 1 Pg. 65-74 ( 2005) ISSN: 1064-1955 [Print] England
• PMID: 16036392 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Membrane Transport Proteins
• RNA, Messenger
• Pregnancy-Associated Plasma Protein-A

Topics

• Adult
• Analysis of Variance
• Base Sequence
• Case-Control Studies
• Female
• Gestational Age
• Humans
• Infant, Newborn
• Infant, Small for Gestational Age
• Membrane Transport Proteins (genetics, metabolism)
• Molecular Sequence Data
• Parity
• Placenta (metabolism)
• Pre-Eclampsia (diagnosis, metabolism)
• Pregnancy
• Pregnancy Outcome
• Pregnancy-Associated Plasma Protein-A (metabolism)
• Prenatal Care
• Probability
• RNA, Messenger (analysis)
• Reference Values
• Reverse Transcriptase Polymerase Chain Reaction (methods)
• Sampling Studies
• Sensitivity and Specificity