Mu opioid receptor in the human endometrium: dynamics of its expression and localization during the menstrual cycle

Lide Totorikaguena, Totorikaguena L, Estíbaliz Olabarrieta, Estibaliz Olabarrieta, Matorras R, Roberto Matorras, Edurne Alonso, Alonso E, Agirregoitia E, Ekaitz Agirregoitia, Naiara Agirregoitia, Agirregoitia N
Fertility and sterility · 2017 · vol. 107(4) , pp. 1070–1077.e1 · doi:10.1016/j.fertnstert.2017.01.020 · PMID:28256208 · W2594589982
Other OA: bronze CC0 ⤵ 4 in-corpus citations
🔓 Open OA copy View on OpenAlex View on PubMed View at publisher
⚙ AI-generated summary by gemini-2.5-flash-lite, 2026-06-07 ⓘ

This study investigated the expression and localization of the mu opioid receptor within the human endometrium across different phases of the menstrual cycle.

One-sentence paraphrase of the abstract; not a substitute for reading it. No clinical advice. How this works

Abstract

OBJECTIVE: To study the dynamics of the expression and localization of the mu opioid receptor (MOR) in human endometrium throughout the menstrual cycle. DESIGN: Analysis of human endometrial samples from different menstrual cycle phases (menstrual, early/midproliferative, late proliferative/early secretory, midsecretory, and late secretory) by reverse transcription-polymerase chain reaction, Western blot, and immunohistochemistry. SETTING: Academic research laboratory. PATIENT(S): Women from the Human Reproduction Unit of the Cruces University Hospital, fulfilling the following criteria: normal uterine vaginal ultrasound; absence of endometriosis, polycystic ovary syndrome, implantation failure, or recurrent miscarriage; and no history of opioid drug use. INTERVENTION(S): Endometrial samples of 86 women categorized into groups for the menstrual cycle phases: 12 menstrual, 21 early/midproliferative, 16 late proliferative/early secretory, 17 midsecretory, and 20 late secretory. MAIN OUTCOME MEASURE(S): MOR gene and protein expression and localization in the different compartments of the human endometrium at different stages of the menstrual cycle. RESULT(S): The expression of MOR mRNA and protein changed throughout the cycle in human endometrium. MOR expression increased during the proliferative phase and decreased during the secretory one. Lower values were found at menstruation, and maximum values around the time of ovulation. Small variations for each endometrial compartment were found. CONCLUSION(S): The presence of MOR in human endometrium and the dynamic changes during the menstrual cycle suggest a possible role for opioids in reproduction events related to the human endometrium or endometriosis.

My notes (saved in your browser only)

MeSH descriptors

Endometrium Menstrual Cycle Receptors, Opioid, mu Adult Adult Blotting, Western Blotting, Western Endometrium Endometrium Female Female Gene Expression Regulation Gene Expression Regulation Hospitals, University Hospitals, University Humans Humans Immunohistochemistry Immunohistochemistry Menstrual Cycle

Citation neighborhood

Papers in the corpus that this work cites (lower rings, blue) and that cite this one (upper rings, green). Dot size scales with the paper's in-corpus citation count — bigger dot = more influential within the endo/adeno field. Click a dot to open that paper. [ expand to 2 hops ] — adds papers reached through this work's immediate citers/citees. Heavier; up to 60 extra dots.

References (38)

Cited by (5)

Source provenance

europepmc
last seen: 2026-10-09T06:09:53.026058+00:00
openalex
last seen: 2026-06-04T00:00:01.174412+00:00
pubmed
last seen: 2026-10-08T21:19:26.535059+00:00
License: CC0 · commercial use OK