Effect of follicle size and dibutyryl cAMP on the cAMP content and gap junctional communication of porcine prepubertal cumulus–oocyte complexes during IVM
Bibliographic record
Abstract
The lower ability of oocytes from prepubertal pigs to yield viable embryos than those from adult pigs appears, in part, a consequence of their reduced ability to accumulate cAMP during IVM. The present study examined the cAMP content of oocytes and cumulus-oocyte complexes (COCs), cumulus expansion and gap junctional communication (GJC) in COCs from 3- and 5-8-mm follicles during IVM. The effect of 1 mm dibutyryl cAMP (db-cAMP) treatment for the first 22 h of IVM was also examined for both follicle size classes. The cAMP concentration of oocytes from 5-8-mm follicles was threefold greater than that in oocytes from 3-mm follicles following 11 h of IVM (11.9 +/- 5.9 v. 3.6 +/- 1.8 fmol, respectively; P < 0.05). In the presence of db-cAMP, the cAMP content of oocytes from 3- and 5-8-mm follicles was no longer significantly different at 11 h IVM. The cAMP concentration of intact COCs from 5-8-mm follicles was significantly higher than that in COCs from 3-mm follicles at 11 h (1110.6 +/- 318.0 v. 116.9 +/- 55.7 fmol, respectively; P < 0.05). Despite maturation with db-cAMP, the cAMP content in COCs from 3- and 5-8-mm follicles at 11 h of IVM remained significantly different (15.1 +/- 4.9 v. 196.2 +/- 33.3 fmol, respectively; P < 0.05). The COCs from 3-mm follicles displayed lower cumulus expansion than did COCs from 5-8-mm follicles at both 11 h (cumulus expansion index (CEI) 1.0 +/- 0.1 v. 1.8 +/- 0.1, respectively; P < 0.01) and 22 h (CEI 1.9 +/- 0.3 v. 2.9 +/- 0.2, respectively; P < 0.05) of IVM. The level of cumulus cell-oocyte GJC decreased during IVM, with the number of GJC significantly greater in COCs from 3-mm compared with 5-8-mm follicles at both 6 h (613 +/- 55 v. 304 +/- 44 fluorescence intensity (FI), respectively; P < 0.05) and 11 h (644 +/- 99 v. 337 +/- 38 FI, respectively; P < 0.05) of IVM. By 22 h of IVM, the GJC of COCs from 3-mm follicles had decreased (227 +/- 18 FI) and was no longer significantly different to that of COCs from 5-8-mm follicles (139 +/- 15 FI; P > 0.05). Dibutyryl cAMP had no effect on the cAMP content, cumulus expansion or GJC of the whole COC. In conclusion, the results of the present study demonstrate that COCs from 3-mm follicles accumulate less intraoocyte and inter-COC cAMP, display lower cumulus expansion and maintain their cumulus cell-oocyte GJC for longer during IVM than do COCs from 5-8-mm follicles.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".