An Involvement of Estrogen Receptors in the Transcriptional and Translational Induction of Growth Hormone Evoked by Xenoestrogens in Rat Pituitary Gland.
Bibliographic record
Abstract
Growth hormone (GH) plays a pivotal role in the regulation of growth, development and body composition. In the previous study, we demonstrated that in vitro exposure to estrogenic endocrine disruptors (EDs) resulted in an increase in GH expression through estrogen receptor (ER) dependent pathways, suggesting that ER appears to be involved in both EDs-induced GH gene transcription and GH secretion in rat pituitary GH3 cells. In order to provide a new insight into in vivo estrogenic ED effects in the GH expression, an immature rat model was employed to determine the potential role of ERs in ED-induced GH expression in rat pituitary gland. At postnatal day 14, immature rats were treated with 4-tert-octyl-phenol (OP), p-nonylphenol (NP) and bisphenol A (BPA) in a dose-dependent manner, the expression levels of GH mRNA and protein were analyzed by a real-time quantitative PCR and Western blot/immunohistochemistry (IHC), respectively. An anti-estrogen, ICI 182,780, was used to examine the potential involvement of ERs in the induction of GH by EDs during critical windows of development. Treatment with a high dose (600 mg/kg body weight [BW]) of OP or NP significantly increased GH mRNA expression at 48 h. OP and NP-induced increase in GH mRNA was completely reversed by co-treatment with ICI 182,780. However, no significant difference was observed by treatment with BPA or co-treatment with an anti-estrogen at the transcriptional levels. Interestingly, exposure to these EDs at a high dose (600 mg/kg BW) markedly enhanced GH protein level in rat pituitary gland, whereas pre-treatment with ICI 182,780 significantly attenuated EDs-induced GH protein. Taken together, we demonstrated for the first time that in vivo exposure to OP, NP or BPA resulted in an increase in GH mRNA and protein levels in rat pituitary gland and the mode of these actions may be involved in an ER-mediated signaling pathway. Thus these results may provide critical evidence in EDs-induced dysregulation of pituitary GH expression and be very important to elucidate the potential impacts of EDs in altered body growth and development as predict the health risk from EDs-exposure to humans and wildlife.
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 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".