POLYUNSATURATED FATTY-ACID ACCRETION IN FIRST-TRIMESTER AND 2ND-TRIMESTER HUMAN FETAL BRAIN - LACK OF CORRELATION WITH LEVELS IN PAIRED PLACENTAL SAMPLES

Accretion of polyunsaturated fatty acids was examined in human fetal b rain and the corresponding placenta from 20 pregnancies covering the g estational ages 9 to 22 weeks to provide data for the first and second trimesters and to complement existing data for the third trimester an d early postnatal periods and also to investigate any correlation betw een the levels of polyunsaturated fatty acids in the developing brain and placenta. Brain polyunsaturated fatty acid (PUFA) accretion was ev ident in the earliest samples. During this early phase of gestation, a gradual increase in brain PUFA levels was noted. Levels of PUFA in th e placental samples were stable during this period. Comparison of PUPA levels from each brain revealed no correlation with PUFA levels in th e corresponding placenta. PUFA accretion in human fetal brain in the s econd trimester, the period of rapid proliferation of neuronal and gli al elements, coincides with the onset of ganglioside accumulation. Alt hough this study provides no direct evidence, finding stable levels of PUFA in placenta is consistent with the current concept that, in the human, the placenta is the principal source of PUFA for export to the fetus throughout gestation. (C) 1996 Academic Press, Inc.