A comparison of the metabolic profiles of fetal and maternal plasma and placenta in normal and diabetic rats by 1H magnetic resonance spectroscopy.

Spectral analysis of spin-echo 1H magnetic resonance spectroscopy (MRS) data has revealed differences in the metabolic profiles of maternal and fetal plasma and placental extracts. Resonances from low-molecular weight components of the normal maternal and fetal plasma were attributed to glucose, lactate, creatine, citrate, amino acids and ketone bodies. There were also signals from lipoprotein molecules associated with lipid-transporting moeties contained in the plasma. The placental extract showed a similar composition to the plasma samples however the spectra were dominated by a large signal attributed to betaine, there was also an absence of signals from citrate, acetoacetate, acetone and lipoproteins. Diabetes caused profound changes in all tissue types indicating high levels of glucose and ketogenic activity. In both the maternal and fetal plasma there were increases in glucose, ketone bodies and valine in the diabetic rats, increases in lactate and alanine were confined to the fetal plasma and placenta. This study indicates that diabetes causes major changes in the composition of fetal plasma which in turn could interfere with the development of the fetus.