Related Experiment Video
Updated: Sep 3, 2026

Ovariectomy and 17β-estradiol Replacement in Rats and Mice: A Visual Demonstration
Published on: June 7, 2012
Unoccupied nuclear oestrogen receptors in the female rat hypothalamus. Increases on oestrogen administration
Abstract:
A major proportion of the hypothalamic nuclear oestrogen receptors were available for complexing with radioactive oestradiol in vitro at 4 degrees C and were apparently unoccupied . At 6 h after oestradiol administration the content of unoccupied nuclear receptors had increased 2.5-fold and represented 71% of the total nuclear receptor content. These results suggest that unoccupied receptors may be active elements in the 'long-term' receptor population of the hypothalamus. Androgenized females had lower contents of these receptors.
More Related Videos
Related Concept Videos
Hormonal Regulation
Oogenesis
Transducer Mechanism: Nuclear Receptors
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
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.
Oogenesis
Each primary oocyte is surrounded by a layer of pre-granulosa cells, forming what is known...
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...

