The concentration of progesterone receptors in rat uterine cytosol and nuclei was measured during the oestrous cycle and pregnancy. The method used allowed the measurement of the total concentration of binding sites (unbound and hormone-bound).
During the oestrous cycle, the concentration of receptors in the cytosol peaked at pro-oestrus, low concentrations were observed at oestrus and metoestrus, and an increase was seen at dioestrus. In the nuclei, maximum concentrations occurred at pro-oestrus and dioestrus. The number of receptors in the cytosol was very low during the first half of pregnancy, but the concentration increased progressively after day 15 to attain a very high level (about 26 000 binding sites/cell) on day 22.
In the nuclei, the concentration of receptors was low at the beginning of pregnancy. On day 5 (day of implantation) there was a slight increase, which corresponded to a decrease in the number of cytosolic receptors and a small peak in the level of progesterone in the plasma. Maximum concentrations were attained during a 'plateau' period between days 9 and 15. Thereafter, there was a decrease in the concentration of nuclear receptors and on day 22, the mean value was very low; in some animals, probably on the verge of parturition, no receptors were detectable in the nuclei.
Journal of Endocrinology is committed to supporting researchers in demonstrating the impact of their articles published in the journal.
The two types of article metrics we measure are (i) more traditional full-text views and pdf downloads, and (ii) Altmetric data, which shows the wider impact of articles in a range of non-traditional sources, such as social media.
More information is on the Reasons to publish page.
| Sept 2018 onwards | Past Year | Past 30 Days | |
|---|---|---|---|
| Full Text Views | 2 | 1 | 0 |
| PDF Downloads | 3 | 0 | 0 |
Online ISSN: 1479-6805
Print ISSN: 0022-0795
Strengthening biomedical communities
to advance science and health
CONTACT US
Bioscientifica Ltd | Starling House | 1600 Bristol Parkway North | Bristol BS34 8YU | UK
Bioscientifica Ltd | Registered in England no 3190519
