Gestational changes in production of NO and expression of NOS mRNA isoforms in the rat placenta.
To monitor changes in NO production over time in the fetal placenta of rats, we used electron paramagnetic resonance spectroscopy with the Fe-N-(dithiocarboxy) sarcosine (Fe-DTCS) complex as an NO-trapping reagent. The expression of nitric oxide synthase (NOS) isoforms was examined in parallel using quantitative RT-PCR. NO production was first detected on day 13.5 of gestation. NO levels reached a peak on day 15.5, then decreased significantly during the last few days of gestation. The pattern of expression of NOS II mRNA was in good agreement with changes in NO levels, whereas NOS III mRNA expression did not change markedly during gestation. Thus, it appears that NO levels in the placenta are NOS II-dependent and differ at different gestational stages.
Graduate School of Veterinary Medicine, Azabu University, Japan.
Takehito
T
Suzuki
Yoshinori
Y
Ikeda
Hiroshi
H
Yoshikawa
Kazuaki
K
Tanaka
Hidetoshi
H
Morita
Masako
M
Yamamoto
Tatsuya
T
Takizawa
D000818:Animals; D004578:Electron Spin Resonance Spectroscopy; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D007527:Isoenzymes; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000096:biosynthesis* / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D010920:Placenta / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D011247:Pregnancy; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction
D004791:Enzyme Inhibitors; D007527:Isoenzymes; D012333:RNA, Messenger; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester