Cyclic changes in epidermal growth factor receptor in human endometrium during menstrual cycle

Area of Science:

• Reproductive biology
• Endocrinology
• Cell signaling

Background:

• Epidermal growth factor (EGF) is a mitogenic peptide found in uterine fluid.
• EGF messenger RNA has been detected in the rat uterus.
• The precise physiological role of EGF in the human uterus remains unclear.

Purpose of the Study:

• To investigate the presence and characteristics of epidermal growth factor (EGF) receptors in human endometrial tissues.
• To understand the regulation of EGF receptor binding throughout the menstrual cycle.

Main Methods:

• Preparation of particulate fractions from human endometrial tissues.
• Epidermal growth factor (EGF) binding assays using radiolabeled EGF.
• Scatchard analysis to determine receptor affinity (Kd) and concentration.
• Quantification of EGF receptor binding across different phases of the menstrual cycle.

Main Results:

• Human endometrial particulate fractions specifically, saturably, and reversibly bind EGF.
• Scatchard analysis revealed a single class of EGF receptor with an apparent Kd of 3.8 x 10(-9) M.
• EGF receptor binding was lowest during menstruation and peaked in the late follicular phase.
• A sharp decrease in EGF receptor binding occurred post-ovulation without altering the Kd.

Conclusions:

• The human endometrium possesses specific receptors for epidermal growth factor (EGF).
• EGF receptor binding exhibits significant cyclic variation, correlating with endometrial proliferation phases.
• These findings suggest a potential role for EGF in the proliferative processes of the human endometrium.