Cytochemically detectable glucose-6-phosphate dehydrogenase is present in human fetal membrane chorion laeve trophoblasts.
We examined the ultrastructural localization of glucose-6-phosphate dehydrogenase (G6PD), a NADPH-generating enzyme, in human fetal membranes at various gestational ages, using newly developed enzyme histochemistry (copper-ferrocyanide method). Electron-dense deposits indicative of G6PD activity were clearly visible in the cytoplasm and on the cytosolic side of the endoplasmic reticulum of chorion laeve cytotrophoblasts at various gestational ages. Positive and negative cytochemical controls ensured specific detection of enzyme activity. These observations indicated that chorion laeve trophoblasts were the site of NADPH production. Chorion laeve trophoblast G6PD may play a significant role in fetal membrane physiology, by delivering NADPH to NADPH-dependent oxidoreductases which these cells possess.
Matsubara
S
S
Department of Obstetrics and Gynecology, Jichi Medical School, Minamikawachi-machi 3311-1, Kawachi-gun, Tochigi 329-0498, Japan. matsushi@jichi.ac.jp
Takizawa
T
T
Takayama
T
T
Iwasaki
R
R
Minakami
H
H
Sato
I
I
D002823:Chorion / Q000201:enzymology* / Q000648:ultrastructure; D003593:Cytoplasm / Q000201:enzymology; D004721:Endoplasmic Reticulum / Q000201:enzymology; D005260:Female; D005865:Gestational Age; D005954:Glucosephosphate Dehydrogenase / Q000032:analysis*; D006651:Histocytochemistry; D006801:Humans; D009249:NADP / Q000378:metabolism; D011247:Pregnancy; D014327:Trophoblasts / Q000201:enzymology* / Q000648:ultrastructure
D009249:NADP; D005954:Glucosephosphate Dehydrogenase