Localization and expression of oxytocin receptor and its messenger ribonucleic acid in peri-implantation phase human endometrium during control and clomiphene-treated cycles.
OBJECTIVE
This study was undertaken to determine expression levels of oxytocin receptor and its gene in peri-implantation phase human endometrium during clomiphene-treated cycles compared with control cycles.


METHODS
Oxytocin receptor and its messenger ribonucleic acid in peri-implantation phase endometrium during control and clomiphene-treated (50 mg days 5 to 9) cycles of 5 healthy fertile women were determined by immunohistochemical methods, Western blot analysis with monoclonal antibody against amino acids 20 through 40 of the extracellular N-terminal human oxytocin receptor, and reverse transcription-polymerase chain reaction with oligonucleotide primers to amplify the 391-base pair fragment of the oxytocin receptor gene.


RESULTS
Oxytocin receptor and its messenger ribonucleic acid were expressed in human peri-implantation phase endometrial samples from both control and clomiphene-treated cycles. The receptor was localized predominantly in the epithelial cells and glands, with little or none detected in the stroma. Oxytocin receptor protein was separated out as a single 70-kd band by Western blot analysis; its relative abundance was significantly reduced during clomiphene-treated cycles. The messenger ribonucleic acid was detected in all endometrium during control and clomiphene-treated cycles, with greater expression during control cycles.


CONCLUSIONS
The expressions of oxytocin receptor and its gene in luteal phase human endometrium suggest a functional relevance in modulation of biochemical changes for implantation.
Division of Reproductive Endocrinology, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Texas Medical School at Houston, Texas, USA.
M Y
MY
Dawood
M
M
Lau
F S
FS
Khan-Dawood
D000328:Adult; D015153:Blotting, Western; D002996:Clomiphene / Q000494:pharmacology*; D017931:DNA Primers; D004717:Endometrium / Q000187:drug effects*; D005260:Female; D005300:Fertility Agents, Female / Q000494:pharmacology*; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D008183:Luteal Phase; D011374:Progesterone / Q000097:blood; D012333:RNA, Messenger / Q000187:drug effects*; D018045:Receptors, Oxytocin / Q000187:drug effects* / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D005300:Fertility Agents, Female; D012333:RNA, Messenger; D018045:Receptors, Oxytocin; D002996:Clomiphene; D011374:Progesterone