3β-Hydroxysteroid dehydrogenase (3β-HSD) activity in bovine cotyledons was much higher than in caruncles throughout the gestation period. The activity of this enzyme in cotyledons increased greatly to 150.6 ± 5.8 pmol min−1 mg−1 protein during the seventh month of gestation, reached a peak of 221.0 ± 34.9 pmol min−1 mg−1 protein during the eighth month, and decreased at parturition. Progesterone and 20α-hydroxyprogesterone concentrations in cotyledons also increased sharply to 2.69 ± 0.30 and 2.15 ± 0.42 ng mg−1 protein, respectively, during the seventh month of gestation, reaching peaks of 2.86 ± 0.47 and 2.51 ± 0.36 ng mg−1 protein, respectively, during the eighth month and decreasing at parturition, in a manner similar to the activity of 3β-hydroxysteroid dehydrogenase. The fluctuation of 17α-hydroxyprogesterone concentration in cotyledons was different from that of progesterone and 20α-hydroxyprogesterone. These findings indicate that the activity of 3β-hydroxysteroid dehydrogenase in the placenta is enhanced during the third trimester, and progesterone synthesized in the cotyledons is converted concurrently to 20α-hydroxyprogesterone before progesterone is transferred to the fetal blood.
Reproduction 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 | 217 | 98 | 4 |
PDF Downloads | 97 | 28 | 0 |