Effects of Dexamethasone Administration to Pregnant Rats on Adenylate Cyclase and Cyclic AMP Phosphodiesterase Activities in the Maternal and Fetal Lungs
Bibliographic record
Abstract
Adenylate cyclase and cyclic AMP phosphodiesterase activities were examined in the maternal and fetal lungs before and after delivery from the saline- and dexamethasone-treated pregnant rats. Basal adenylate cyclase activity in the maternal lungs of control animals did not change after parturition whereas the enzyme activity in fetal lungs increased 2.5-fold after birth. Dexamethasone treatment reduced adenylate cyclase activity in the maternal lungs before and after parturition while the enzyme activity in fetal lungs was increased. The ability of the cytoplasmic factors to activate adenylate cyclase in maternal lungs decreased after parturition. Dexamethasone treatment of the pregnant rat lowered the cytoplasmic activation of the maternal enzyme before and after parturition, but the percent activation of the enzyme in both the maternal and fetal lungs was not affected. The decrease in activator activity of the maternal lungs after parturition was not apparently due to the reduced sensitivity of adenylate cyclase to the same level of the activator protein. However, it would appear that both adenylate cyclase and its activator protein have undergone some maturational changes during lung development. Adrenalectomy of rats did not alter the basal adenylate cyclase activity in lung membranes but reduced the cytoplasmic activation of the enzyme. Unlike pregnant rats, dexamethasone treatment of adrenalectomized rats restored the cytoplasmic activation of adenylate cyclase not only to the control value, but potentiated it even higher than the control without affecting the basal adenylate cyclase activity. Cyclic AMP phosphodiesterase activity in both the maternal and fetal lungs was not influenced by parturition. However, dexamethasone treatment lowered cyclic AMP phosphodiesterase activity in both the maternal and fetal lungs at both ages. Dexamethasone treatment of pregnant rats elevated phospholipids and lowered DNA levels in the maternal as well as fetal lungs. These data are consistent with the view that dexamethasone treatment of pregnant rats during late gestation may elevate cyclic AMP levels to induce fetal lung maturation with a concomitant decrease in cellular proliferation.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| 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 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".