DEVELOPMENTAL-CHANGES OF GENE-EXPRESSION IN HEME METABOLIC ENZYMES INRAT PLACENTA

Transcription levels of the non-specific delta-aminolevulinate synthas e (ALAS-N) and heme oxygenase-1 (HO-1) in the placenta at the terminal stage of pregnancy mere comparable to those in the female adult liver and in the spleen, respectively. Immunohistochemical studies demonstr ated that both enzymes mere exclusively expressed in the trophoblast. During gestation, transcript of ALAS-N slightly increased, while HO-1 mRNA significantly decreased. Induced acute fetal hypoxia resulted in an increase in ALAS-N mRNA and in a decrease in HO-1 mRNA. These findi ngs indicate that placental heme metabolism is influenced by the oxyge n supply. (C) 1998 Federation of European Biochemical Societies.