Cyclooxygenase-1 and -2 in human placenta and placental bed after normal and pre-eclamptic pregnancies.
In pre-eclampsia, the ratio of prostacyclin:thromboxane production rate is decreased favouring the vasoconstrictive thromboxane. One of the rate-limiting steps in prostaglandin synthesis is cyclooxygenase (COX) activity. Therefore, we investigated the expression of COX-1 and COX-2 in human placenta and placental bed. Tissue specimens from the 29th to 40th week of pregnancy were obtained from Caesarean sections after uncomplicated and pre-eclamptic pregnancies before the onset of labour. COX-1 and COX-2 were localized immunohistochemically with the identification of positive cells by double immunofluorescence staining. The protein and mRNA levels were analysed by immunoblotting and quantitative reverse transcriptase-polymerase chain reaction. Expression of both COX-1 and COX-2 could be observed in placenta and placental bed. COX-1-like immunoreactivity was observed in most cell types with strongest staining in macrophages. Only macrophages, endothelium, vascular leiomyocytes and fibroblasts stained positively for COX-2. In placenta, COX-1 and -2 expression was unchanged after pre-eclampsia. In placental bed, protein and mRNA levels of COX-1 were increased in the pre-eclamptic group (P < 0.05), whereas COX-2 expression did not differ significantly from normal pregnancies. An increased expression of COX-1 could be involved in the pathophysiology of pre-eclamptic changes within the placental bed. A therapy with drugs inhibiting COX-1 might be beneficial in this condition.
Wetzka
B
B
Endocrinology and Reproductive Medicine, Universitätsfrauenklinik Freiburg, Germany.
Nüsing
R
R
Charnock-Jones
D S
DS
Schäfer
W
W
Zahradnik
H P
HP
Smith
S K
SK
D015153:Blotting, Western; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D003656:Decidua / Q000201:enzymology; D004730:Endothelium, Vascular / Q000201:enzymology; D005260:Female; D005347:Fibroblasts / Q000201:enzymology; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000032:analysis* / Q000235:genetics; D008264:Macrophages / Q000201:enzymology; D008565:Membrane Proteins; D009130:Muscle, Smooth / Q000201:enzymology; D010920:Placenta / Q000201:enzymology*; D011225:Pre-Eclampsia / Q000201:enzymology*; D011247:Pregnancy; D011451:Prostaglandin-Endoperoxide Synthases / Q000032:analysis* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D014327:Trophoblasts / Q000201:enzymology
D007527:Isoenzymes; D008565:Membrane Proteins; D012333:RNA, Messenger; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C496511:PTGS1 protein, human; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases