English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

To determine whether prostaglandin G/H synthase-2 (PGHS-2) induction occurs under physiological conditions, heifers were ovariectomized and preovulatory follicles were isolated 0 (n = 4), 18 (n = 4), and 24 h (n = 4) after the onset of estrus. The time of the LH surge was determined in blood samples collected every 4 h pre- and postestrus. Preparations of follicle wall and isolated theca interna and granulosa cells were analyzed for PGHS-2 protein and mRNA by immunoblot and Northern blot, respectively. Immunohistochemistry was used to document the in situ localization of PGHS-2 protein, and follicular fluid concentrations of prostaglandin (PG) E2 and PGF2alpha were determined to monitor changes in PG synthetic activities. Results showed that PGHS-2 mRNA (4.0 kilobases) and protein (74000 Mr) were absent in preovulatory follicles isolated at the onset of estrus, low in follicles obtained 18 h after estrus (16.0 +/- 1.2 h post-LH surge), and markedly induced 24 h postestrus (20 +/- 0 h post-LH surge). Immunoblot and immunohistochemical analyses revealed that PGHS-2 protein was selectively induced in granulosa cells. Follicular fluid concentrations of PGE2 and PGF2alpha increased significantly (p &lt; 0.01) between 0 and 24 h after estrus (from 2.8 +/- 0.2 to 87.9 +/- 30.9 ng/ml for PGE2; from 0.05 +/- 0.02 to 68.9 +/- 23.6 ng/ml for PGF2alpha). Collectively, these results clearly demonstrate that the induction of PGHS-2 in bovine preovulatory follicles is a physiological event that occurs after the endogenous LH surge.

Prostaglandin G/H Synthase-2 is Expressed in Bovine Preovulatory Follicles after the Endogenous Surge of Luteinizing Hormone1