Related Experiment Video
Updated: Oct 20, 2026

Performing Vaginal Lavage, Crystal Violet Staining, and Vaginal Cytological Evaluation for Mouse Estrous Cycle Staging Identification
Published on: September 15, 2012
Levels of estrogen and progesterone receptor in human endometrium during the menstrual cycle
Abstract:
Receptors for estrogens and progesterone have been assayed in 24 samples of normal human endometria at different phases of the menstrual cycle. In the proliferative endometrium the concentration of estrogen binding sites was significantly higher than that of progesterone receptor while, in the secretive endometrium, the concentration of estrogen receptor was low, compared to that of progesterone receptor. The highest concentration of both receptors was observed during the periovulatory period. From the correlation observed between estrogen and progesterone receptors and the levels of the respective steroids in the plasma, it is suggested that the levels of plasma estradiol or its own tissue receptor determine the synthesis of progesterone receptors in the periovulatory period.
Related Concept Videos
Hormonal Regulation of the Menstrual Cycle
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.
Ovarian Cycle
Hormonal Control of the Ovarian Cycle
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...
The Menstrual Cycle
The menstrual phase occurs from days 1 to 5 and involves the shedding of the stratum functionalis, as a uterine...
Proliferative Phase
Notably, the stratum basale, the basal layer of the endometrium, including the basal parts of the uterine glands, remains unaffected by menstruation. Stem cells in this layer undergo mitosis, regenerating the stratum functionalis and thickening the...
Secretory Phase
Following ovulation, the corpus luteum, a temporary endocrine structure, produces progesterone and estrogens. These hormones stimulate the growth and coiling of endometrial...

