The influence of sex and neonatal stress on medullary microglia in rat pups
Bibliographic record
Abstract
New Findings What is the central question of the study ? Does neonatal stress, in the form of neonatal maternal separation, influence the maturation of microglial density, morphology and neuronal signalling in medullary regions regulating cardiorespiratory function in rat pups? What is the main finding and its importance ? Using Iba‐1 immunohistochemistry, we show that neonatal maternal separation augments microglial density and the proportion of cells with an amoeboid morphology in the medulla. Although the current understanding of the effect of early life stress on medullary development is relatively limited, these data show that within this area, microglia are affected by neonatal stress. Microglia could therefore be important effectors in cardiorespiratory disorders resulting from maternal separation. A bstract Neonatal stress has wide‐ranging consequences for the developing brain, including the medullary cardiorespiratory network. In rat pups, the reflexive cardiorespiratory inhibition triggered by the presence of liquids near the larynx is augmented by neonatal maternal separation (NMS), especially in males. Sex‐specific enhancement of synaptic connectivity by NMS might explain this cardiorespiratory dysfunction. Microglia influence the formation, maturation, activity and elimination of developing synapses, but their role in the wiring of medullary networks is unknown. Owing to their sensitivity to sex hormones and stress hormones, microglial dysfunction could contribute to the abnormal cardiorespiratory phenotype observed in NMS pups. Here, we first used ionized calcium‐binding adapter molecule‐1 (Iba‐1) immunolabelling to compare the density and morphology of microglia in the medulla of male versus female rat pups (14–15 days old) that were either undisturbed or subjected to NMS (3 h day −1 ; postnatal days 3–12). Neonatal maternal separation augmented the density of Iba‐1 + cells (caudal region of the NTS), increased the size of the soma and reduced the arborization area (especially in the dorsal motor nucleus of the vagus). Sex‐based differences were not observed. Given that the actions of microglia are regulated by neuronal fractalkine (CX 3 CL 1 ), we then used western blot analysis to compare the expression of CX 3 CL 1 and its microglial receptor (CX 3 CR 1 ) in medullary homogenates from control and NMS pups. Although CX 3 CR 1 expression was 59% greater in males versus females, NMS had no effect on CX 3 CL 1 /CX 3 CR 1 signalling. Given that an amoeboid morphology reflects an immature phenotype in developing microglia, NMS could interfere with synaptic pruning via a different mechanism.
Stored with the screening record, where it is evidence for the labels above.
How this classification was reachedexpand
The three-model screen
all 5,600 screened works →All three models called this out of scope.
Animal experiment on neonatal stress and medullary microglia.
It experimentally studies microglia in rat pups rather than research practice.
Basic neuroscience of neonatal stress and medullary microglia in rats, not research-on-research.
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".