Temporal analysis of connexin43 protein and gene expression throughout the menstrual cycle in human endometrium

Objective: To analyze the pattern of connexin43 gene and protein expression in human endometrium throughout the menstrual cycle. Design: Controlled clinical study. Setting: An academic research center. Patient(s): Women with 28-day menstrual cycles who had mechanical infertility and failed to conceive after IVF treatment. Intervention(s): Endometrial and blood samples were collected on days 8, 12, 14, 21, and 25 of spontaneous menstrual cycles. Main Outcome Measure(s): Endometrial expression of connexin43 protein and messenger RNA, endometrial thickness, and serum concentrations of gonadotropins and steroids. Result(s): The expression of connexin43 gene and protein decreased on day 12 and day 14 of the menstrual cycle and then increased on day 21 and day 25, respectively. A serum LH surge accompanied by a peak in the FSH concentration was observed on days 12-14. The progesterone concentration increased on days 21-25, but there was no significant change in the E-2 concentration. The thickness of the endometrium increased between days 8 and 12 and did not change further between days 21 and 25. Conclusion(s): The expression of connexin43 gene and protein in human endometrium changes during the menstrual cycle in a pattern that is associated with the secretion of LH, FSH, and progesterone. This pattern may serve as a marker for implantation competence. (Fertil Steril(R) 2000;73:381-6. (C)2000 by American Society for Reproductive Medicine.).