In vitro and in vivo Growth Hormone Responsiveness to Growth Hormone-Releasing Factor in Male and Female Zucker Rats
Bibliographic record
Abstract
In order to determine whether there is an anomaly in the pituitary responsiveness to growth hormone (GH)-releasing factor in the genetically obese rat, we examined the in vitro and in vivo effects of rGRF(1-29)NH2 (GRF) on GH release in male and female Zucker rats. The effect of increasing GRF concentrations (1.56, 6.25, 12.5 25 and 50 pM) was first tested on GH release from freshly perifused anterior pituitary cells. In both sexes, the GH response per one pituitary equivalent to each GRF concentration tested was reduced in the obese group. However, when GH release was expressed as a percent of initial cell GH content, there was no difference between the lean and the obese groups. Furthermore, under pentobarbital anesthesia, GRF was injected intravenously at two consecutive doses of 0.8 and 4.0 microgram/kg body weight in obese and lean animals. In both sexes, the GH response to each dose of GRF tested was decreased in the obese group. Basal serum GH concentrations were similar in male and female obese rats compared to their respective lean siblings. In conclusion, this study demonstrates a decrease of the in vitro and in vivo pituitary response to GRF in the obese Zucker rat, suggesting a possible secondary defect at the pituitary level.
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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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
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".