Expression of human prostaglandin transporter in the human endometrium across the menstrual cycle.
Prostaglandins (PGs) are important regulators of reproductive function. The mechanism by which PGs are transported across the biological membrane is a new emerging field of investigation. Prostaglandin transporter (PGT) has been identified as a functional PG carrier. The aim of our study was to outline the expression of PGT in the human endometrium across the menstrual cycle. Quantitative RT-PCR showed human PGT (hPGT) expression to be strong in the proliferative and early secretory phases and low in the middle to late secretory phase. Northern blot analysis revealed hPGT mRNA transcript of 4 kb in the human endometrium. A peptide-directed polyclonal antibody was generated in rabbits against the 22 amino acids forming the C terminus of hPGT. Antibody specificity was demonstrated by Western blot. Immunoblots of endogenous hPGT in the human endometrium revealed a 70-kDa protein in endometrial cells. Endometrial biopsies collected across the menstrual cycle were used to assess hPGT protein expression by immunohistochemistry. hPGT was immunolocalized to luminal, glandular epithelial, and stromal cells. Because it was observed at the mRNA level, semiquantitative analysis showed a higher protein expression in proliferative and early secretory phases than in the mid-late secretory phase. In conclusion, our study revealed that hPGT expression is modulated in epithelial and stromal cells of the human endometrium at both mRNA and protein levels during the menstrual cycle. These findings support a role for hPGT as an important new player in the regulation of PG action in the human endometrium.
Kang
Jihong
J
Unité de Recherche en Ontogénie et Reproduction, Centre Hospitalier Universitaire de Québec, Université Laval, 2705, Boulevard Laurier, Sainte-Foy, Québec G1V 4G2, Canada.
Chapdelaine
Pierre
P
Parent
Julie
J
Madore
Eric
E
Laberge
Philippe Y
PY
Fortier
Michel A
MA
D017920:Antiporters / Q000032:analysis / Q000235:genetics* / Q000502:physiology; D002478:Cells, Cultured; D051546:Cyclooxygenase 2; D004268:DNA-Binding Proteins / Q000032:analysis / Q000235:genetics* / Q000502:physiology; D004717:Endometrium / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007375:Interleukin-1 / Q000494:pharmacology; D008565:Membrane Proteins; D008597:Menstrual Cycle / Q000378:metabolism*; D027361:Organic Anion Transporters; D011451:Prostaglandin-Endoperoxide Synthases / Q000032:analysis; D011453:Prostaglandins / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis
D017920:Antiporters; D004268:DNA-Binding Proteins; D007375:Interleukin-1; D008565:Membrane Proteins; D027361:Organic Anion Transporters; D011453:Prostaglandins; D012333:RNA, Messenger; C503526:SLCO2A1 protein, human; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases