AMPA and NMDA Receptors Regulate Responses of Neurons in the Rat's Inferior Colliculus
Bibliographic record
Abstract
The contribution of N-methyl-D-aspartate (NMDA) and AMPA receptors to auditory responses in the rat's inferior colliculus was examined by recording single-unit activity before, during, and after local iontophoretic application of receptor-specific antagonists. Tone bursts and sinusoidal amplitude modulated sounds were presented to one ear, and recordings were made from the contralateral central nucleus of inferior colliculus (ICC). The receptor specific antagonists, (+/-)-3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP) for NMDA receptors and 1,2,3,4-tetrahydro-6-nitro-2,3-dioxo-benzo[f]quinoxaline-7-sulfonamide (NBQX) for AMPA receptors, were released at the recording site through a multi-barreled pipette. For most neurons, either CPP or NBQX alone resulted in a reversible reduction in the number of action potentials evoked by tonal stimulation. For neurons with an onset response pattern, NBQX either completely eliminated or greatly reduced the number of action potentials. CPP also reduced the number of action potentials but had a less pronounced effect than NBQX. For neurons with a sustained firing pattern, NBQX reduced the total number of action potentials, but had a preferential effect on the early part (first 10-20 ms) of the response. CPP also resulted in a reduction in the total number of action potentials, but had a more pronounced effect on the later part (>20 ms) of the response. These results indicate that both AMPA and NMDA receptors contribute to sound evoked excitatory responses in the ICC. They have a selective influence on early and late components of tone-evoked responses. Both receptor types are involved in generating excitatory responses across a wide range of sound pressure levels as indicated by rate level functions obtained before and during drug application. In addition, both CPP and NBQX reduced responses to sinusoidal amplitude modulated sounds. The synchrony of firing to the modulation envelope as measured by vector strength at different rates of modulation was not greatly affected by either CPP or NBQX in spite of the decrease in firing rate.
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) | 0.001 | 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".